{
  "openapi": "3.1.0",
  "info": {
    "title": "Haldir API — Governance for AI Agents",
    "version": "0.1.0",
    "description": "Haldir is a security and governance layer for AI agents, composed of three modules:\n\n- **Gate** — Session-scoped permissions. Create short-lived sessions with explicit scopes (read, write, admin, spend:N) and TTLs. Every privileged operation must pass through Gate first.\n- **Vault** — Encrypted secret storage with access control. Secrets are AES-encrypted at rest and only released to sessions that hold the required scope. Vault also manages spend budgets and payment authorization.\n- **Watch** — Tamper-evident audit logging with automatic anomaly detection. Every tool call, payment, and decision is recorded. Suspicious patterns (rapid-fire actions, high-cost operations, unusual tools) are flagged in real time.\n\nAuthenticate with `Authorization: Bearer hld_...` or `X-API-Key: hld_...`. Create your first key via `POST /v1/keys` (no auth required for the bootstrap key).",
    "contact": {
      "name": "0xN0rD",
      "url": "https://haldir.xyz"
    },
    "license": {
      "name": "MIT",
      "url": "https://opensource.org/licenses/MIT"
    }
  },
  "servers": [
    {
      "url": "https://haldir.xyz",
      "description": "Production"
    }
  ],
  "security": [
    { "BearerAuth": [] },
    { "ApiKeyAuth": [] }
  ],
  "tags": [
    { "name": "gate", "description": "Session management and permission checks" },
    { "name": "vault", "description": "Encrypted secret storage and retrieval" },
    { "name": "watch", "description": "Audit logging and spend tracking" },
    { "name": "proxy", "description": "Governance proxy for upstream MCP servers" },
    { "name": "audit", "description": "Query audit trail and spend summaries" },
    { "name": "approvals", "description": "Human-in-the-loop approval workflows" },
    { "name": "webhooks", "description": "Webhook registration for real-time alerts" }
  ],
  "paths": {
    "/v1/keys": {
      "post": {
        "operationId": "createApiKey",
        "summary": "Create an API key",
        "description": "Create a new API key. The very first key requires no authentication. Subsequent keys require either a valid API key or the HALDIR_BOOTSTRAP_TOKEN.",
        "tags": ["gate"],
        "security": [
          {},
          { "BearerAuth": [] },
          { "ApiKeyAuth": [] }
        ],
        "requestBody": {
          "required": false,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "name": {
                    "type": "string",
                    "default": "default",
                    "description": "Human-readable name for this key"
                  },
                  "tier": {
                    "type": "string",
                    "enum": ["free", "pro", "enterprise"],
                    "default": "free",
                    "description": "Pricing tier (affects rate limits)"
                  },
                  "bootstrap_token": {
                    "type": "string",
                    "description": "HALDIR_BOOTSTRAP_TOKEN value, required when creating additional keys without an existing API key"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "API key created",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "key": { "type": "string", "description": "Full API key (shown only once)" },
                    "prefix": { "type": "string", "description": "Key prefix for identification" },
                    "name": { "type": "string" },
                    "tier": { "type": "string" },
                    "message": { "type": "string" }
                  },
                  "required": ["key", "prefix", "name", "tier", "message"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" }
        }
      }
    },
    "/v1/sessions": {
      "post": {
        "operationId": "createSession",
        "summary": "Create an agent session",
        "description": "Create a scoped session for an AI agent with explicit permissions, TTL, and optional spend budget.",
        "tags": ["gate"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["agent_id"],
                "properties": {
                  "agent_id": { "type": "string", "description": "Unique agent identifier" },
                  "scopes": {
                    "type": "array",
                    "items": { "type": "string" },
                    "default": ["read", "browse"],
                    "description": "Permission scopes to grant"
                  },
                  "ttl": {
                    "type": "integer",
                    "default": 3600,
                    "description": "Session time-to-live in seconds"
                  },
                  "spend_limit": {
                    "type": "number",
                    "nullable": true,
                    "description": "Maximum USD spend for this session"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Session created",
            "content": {
              "application/json": {
                "schema": { "$ref": "#/components/schemas/SessionCreated" }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/sessions/{session_id}": {
      "get": {
        "operationId": "getSession",
        "summary": "Get session info",
        "description": "Retrieve the current state of a session including scopes, spend, remaining budget, and validity.",
        "tags": ["gate"],
        "parameters": [
          { "$ref": "#/components/parameters/SessionIdPath" }
        ],
        "responses": {
          "200": {
            "description": "Session details",
            "content": {
              "application/json": {
                "schema": { "$ref": "#/components/schemas/SessionDetail" }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "404": { "$ref": "#/components/responses/NotFound" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "delete": {
        "operationId": "revokeSession",
        "summary": "Revoke a session",
        "description": "Immediately revoke a session, permanently disabling all permissions.",
        "tags": ["gate"],
        "parameters": [
          { "$ref": "#/components/parameters/SessionIdPath" }
        ],
        "responses": {
          "200": {
            "description": "Session revoked",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "revoked": { "type": "boolean", "const": true },
                    "session_id": { "type": "string" }
                  },
                  "required": ["revoked", "session_id"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "404": { "$ref": "#/components/responses/NotFound" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/sessions/{session_id}/check": {
      "post": {
        "operationId": "checkPermission",
        "summary": "Check a session permission",
        "description": "Check whether a session holds a specific scope. Use before sensitive operations to avoid 403 errors.",
        "tags": ["gate"],
        "parameters": [
          { "$ref": "#/components/parameters/SessionIdPath" }
        ],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["scope"],
                "properties": {
                  "scope": { "type": "string", "description": "The scope to check (e.g. read, write, admin)" }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Permission check result",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "allowed": { "type": "boolean" },
                    "session_id": { "type": "string" },
                    "scope": { "type": "string" }
                  },
                  "required": ["allowed", "session_id", "scope"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/secrets": {
      "post": {
        "operationId": "storeSecret",
        "summary": "Store an encrypted secret",
        "description": "Store a secret in the Vault, encrypted at rest with AES. Optionally require a specific scope for retrieval.",
        "tags": ["vault"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["name", "value"],
                "properties": {
                  "name": { "type": "string", "description": "Unique secret name" },
                  "value": { "type": "string", "description": "Secret value to encrypt" },
                  "scope_required": {
                    "type": "string",
                    "default": "read",
                    "description": "Minimum scope a session must hold to read this secret"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Secret stored",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "stored": { "type": "boolean", "const": true },
                    "name": { "type": "string" }
                  },
                  "required": ["stored", "name"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "get": {
        "operationId": "listSecrets",
        "summary": "List secret names",
        "description": "List all stored secret names (never values).",
        "tags": ["vault"],
        "responses": {
          "200": {
            "description": "List of secret names",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "secrets": {
                      "type": "array",
                      "items": { "type": "string" }
                    },
                    "count": { "type": "integer" }
                  },
                  "required": ["secrets", "count"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/secrets/{name}": {
      "get": {
        "operationId": "getSecret",
        "summary": "Retrieve a secret",
        "description": "Retrieve a decrypted secret. Pass X-Session-ID header or session_id query param for scope-based access control.",
        "tags": ["vault"],
        "parameters": [
          {
            "name": "name",
            "in": "path",
            "required": true,
            "schema": { "type": "string" },
            "description": "Secret name"
          },
          {
            "name": "session_id",
            "in": "query",
            "required": false,
            "schema": { "type": "string" },
            "description": "Session ID for scope enforcement"
          },
          {
            "name": "X-Session-ID",
            "in": "header",
            "required": false,
            "schema": { "type": "string" },
            "description": "Session ID for scope enforcement (alternative to query param)"
          }
        ],
        "responses": {
          "200": {
            "description": "Secret value",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "name": { "type": "string" },
                    "value": { "type": "string" }
                  },
                  "required": ["name", "value"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "403": { "$ref": "#/components/responses/Forbidden" },
          "404": { "$ref": "#/components/responses/NotFound" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "delete": {
        "operationId": "deleteSecret",
        "summary": "Delete a secret",
        "description": "Permanently delete a secret from the Vault.",
        "tags": ["vault"],
        "parameters": [
          {
            "name": "name",
            "in": "path",
            "required": true,
            "schema": { "type": "string" },
            "description": "Secret name"
          }
        ],
        "responses": {
          "200": {
            "description": "Secret deleted",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "deleted": { "type": "boolean", "const": true },
                    "name": { "type": "string" }
                  },
                  "required": ["deleted", "name"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "404": { "$ref": "#/components/responses/NotFound" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/payments/authorize": {
      "post": {
        "operationId": "authorizePayment",
        "summary": "Authorize a payment",
        "description": "Authorize a payment against a session's spend budget. Denied if insufficient budget remains.",
        "tags": ["vault"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["session_id", "amount"],
                "properties": {
                  "session_id": { "type": "string" },
                  "amount": { "type": "number", "description": "Amount to authorize" },
                  "currency": { "type": "string", "default": "USD", "description": "ISO 4217 currency code" },
                  "description": { "type": "string", "default": "", "description": "What the payment is for" }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Payment authorized",
            "content": {
              "application/json": {
                "schema": { "$ref": "#/components/schemas/PaymentResult" }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "403": {
            "description": "Payment denied (budget exceeded)",
            "content": {
              "application/json": {
                "schema": { "$ref": "#/components/schemas/PaymentResult" }
              }
            }
          },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/audit": {
      "post": {
        "operationId": "logAction",
        "summary": "Log an agent action",
        "description": "Log an action to the tamper-evident audit trail. Watch automatically flags anomalous patterns.",
        "tags": ["watch", "audit"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["session_id", "action"],
                "properties": {
                  "session_id": { "type": "string" },
                  "tool": { "type": "string", "default": "", "description": "Tool or service name" },
                  "action": { "type": "string", "description": "Description of the action" },
                  "details": { "type": "string", "nullable": true, "description": "Additional context" },
                  "cost_usd": { "type": "number", "default": 0, "description": "Cost in USD" }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Action logged",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "logged": { "type": "boolean", "const": true },
                    "entry_id": { "type": "string" },
                    "flagged": { "type": "boolean", "description": "Whether the action was flagged as anomalous" },
                    "flag_reason": { "type": "string", "nullable": true }
                  },
                  "required": ["logged", "entry_id", "flagged", "flag_reason"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "get": {
        "operationId": "getAuditTrail",
        "summary": "Query the audit trail",
        "description": "Retrieve audit log entries with optional filters by session, agent, tool, or flagged status.",
        "tags": ["watch", "audit"],
        "parameters": [
          { "name": "session_id", "in": "query", "schema": { "type": "string" }, "description": "Filter by session" },
          { "name": "agent_id", "in": "query", "schema": { "type": "string" }, "description": "Filter by agent" },
          { "name": "tool", "in": "query", "schema": { "type": "string" }, "description": "Filter by tool name" },
          { "name": "flagged", "in": "query", "schema": { "type": "string", "enum": ["true", "false"] }, "description": "Only flagged entries" },
          { "name": "limit", "in": "query", "schema": { "type": "integer", "default": 100 }, "description": "Max entries to return" }
        ],
        "responses": {
          "200": {
            "description": "Audit entries",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "count": { "type": "integer" },
                    "entries": {
                      "type": "array",
                      "items": { "$ref": "#/components/schemas/AuditEntry" }
                    }
                  },
                  "required": ["count", "entries"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/audit/spend": {
      "get": {
        "operationId": "getSpend",
        "summary": "Get spend summary",
        "description": "Get aggregated spend data, optionally filtered by session or agent.",
        "tags": ["watch", "audit"],
        "parameters": [
          { "name": "session_id", "in": "query", "schema": { "type": "string" }, "description": "Filter by session" },
          { "name": "agent_id", "in": "query", "schema": { "type": "string" }, "description": "Filter by agent" }
        ],
        "responses": {
          "200": {
            "description": "Spend summary",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "description": "Spend breakdown returned by Watch.get_spend()",
                  "additionalProperties": true
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/usage": {
      "get": {
        "operationId": "getUsage",
        "summary": "Get usage stats",
        "description": "Get API usage count for the current tenant, optionally for a specific month.",
        "tags": ["watch"],
        "parameters": [
          { "name": "month", "in": "query", "schema": { "type": "string", "pattern": "^\\d{4}-\\d{2}$" }, "description": "Month in YYYY-MM format (defaults to current month)" }
        ],
        "responses": {
          "200": {
            "description": "Usage data",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "tenant_id": { "type": "string" },
                    "month": { "type": "string" },
                    "action_count": { "type": "integer" },
                    "tier": { "type": "string" }
                  },
                  "required": ["tenant_id", "month", "action_count"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/approvals/rules": {
      "post": {
        "operationId": "addApprovalRule",
        "summary": "Add an approval rule",
        "description": "Add a rule that triggers human-in-the-loop approval for matching actions.",
        "tags": ["approvals"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["type"],
                "properties": {
                  "type": {
                    "type": "string",
                    "enum": ["spend_over", "tool_blocked", "destructive", "all"],
                    "description": "Rule type"
                  },
                  "threshold": { "type": "number", "default": 0, "description": "Threshold for spend_over rules (USD)" },
                  "tools": {
                    "type": "array",
                    "items": { "type": "string" },
                    "nullable": true,
                    "description": "Tool names for tool_blocked rules"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Rule added",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "added": { "type": "boolean", "const": true },
                    "type": { "type": "string" }
                  },
                  "required": ["added", "type"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/approvals/request": {
      "post": {
        "operationId": "requestApproval",
        "summary": "Request human approval",
        "description": "Submit an action for human approval. The agent polls the approval status until it is approved or denied.",
        "tags": ["approvals"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["session_id"],
                "properties": {
                  "session_id": { "type": "string" },
                  "tool": { "type": "string", "default": "" },
                  "action": { "type": "string", "default": "" },
                  "amount": { "type": "number", "default": 0 },
                  "reason": { "type": "string", "default": "" },
                  "details": { "type": "string", "nullable": true },
                  "ttl": { "type": "integer", "default": 3600, "description": "Time before the request expires (seconds)" }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Approval requested",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "request_id": { "type": "string" },
                    "status": { "type": "string" },
                    "expires_at": { "type": "number" }
                  },
                  "required": ["request_id", "status", "expires_at"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/approvals/{request_id}": {
      "get": {
        "operationId": "checkApproval",
        "summary": "Check approval status",
        "description": "Poll the status of a pending approval request.",
        "tags": ["approvals"],
        "parameters": [
          {
            "name": "request_id",
            "in": "path",
            "required": true,
            "schema": { "type": "string" }
          }
        ],
        "responses": {
          "200": {
            "description": "Approval status",
            "content": {
              "application/json": {
                "schema": { "$ref": "#/components/schemas/ApprovalDetail" }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "404": { "$ref": "#/components/responses/NotFound" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/approvals/{request_id}/approve": {
      "post": {
        "operationId": "approveRequest",
        "summary": "Approve a pending request",
        "description": "Approve a pending approval request, allowing the agent to proceed.",
        "tags": ["approvals"],
        "parameters": [
          {
            "name": "request_id",
            "in": "path",
            "required": true,
            "schema": { "type": "string" }
          }
        ],
        "requestBody": {
          "required": false,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "decided_by": { "type": "string", "default": "", "description": "Who approved (e.g. human operator name)" },
                  "note": { "type": "string", "default": "", "description": "Optional note on the decision" }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Request approved",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "approved": { "type": "boolean", "const": true },
                    "request_id": { "type": "string" }
                  },
                  "required": ["approved", "request_id"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/approvals/{request_id}/deny": {
      "post": {
        "operationId": "denyRequest",
        "summary": "Deny a pending request",
        "description": "Deny a pending approval request, blocking the agent's action.",
        "tags": ["approvals"],
        "parameters": [
          {
            "name": "request_id",
            "in": "path",
            "required": true,
            "schema": { "type": "string" }
          }
        ],
        "requestBody": {
          "required": false,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "decided_by": { "type": "string", "default": "" },
                  "note": { "type": "string", "default": "" }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Request denied",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "denied": { "type": "boolean", "const": true },
                    "request_id": { "type": "string" }
                  },
                  "required": ["denied", "request_id"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/approvals/pending": {
      "get": {
        "operationId": "listPendingApprovals",
        "summary": "List pending approvals",
        "description": "List all approval requests that are still pending a decision.",
        "tags": ["approvals"],
        "parameters": [
          { "name": "agent_id", "in": "query", "schema": { "type": "string" }, "description": "Filter by agent" }
        ],
        "responses": {
          "200": {
            "description": "Pending approval requests",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "count": { "type": "integer" },
                    "requests": {
                      "type": "array",
                      "items": { "$ref": "#/components/schemas/PendingApproval" }
                    }
                  },
                  "required": ["count", "requests"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/webhooks": {
      "post": {
        "operationId": "registerWebhook",
        "summary": "Register a webhook",
        "description": "Register a URL to receive real-time event notifications (anomaly, approval_requested, budget_exhausted).",
        "tags": ["webhooks"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["url"],
                "properties": {
                  "url": { "type": "string", "format": "uri", "description": "Webhook endpoint URL" },
                  "name": { "type": "string", "default": "", "description": "Human-readable name" },
                  "events": {
                    "type": "array",
                    "items": { "type": "string", "enum": ["all", "anomaly", "approval_requested", "budget_exhausted"] },
                    "nullable": true,
                    "description": "Events to subscribe to (defaults to all)"
                  }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Webhook registered",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "registered": { "type": "boolean", "const": true },
                    "url": { "type": "string" },
                    "events": {
                      "type": "array",
                      "items": { "type": "string" },
                      "nullable": true
                    }
                  },
                  "required": ["registered", "url", "events"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "get": {
        "operationId": "listWebhooks",
        "summary": "List registered webhooks",
        "description": "List all webhooks registered for this account.",
        "tags": ["webhooks"],
        "responses": {
          "200": {
            "description": "Webhook list",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "webhooks": { "type": "array", "items": { "type": "object" } }
                  },
                  "required": ["webhooks"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/proxy/upstreams": {
      "post": {
        "operationId": "registerUpstream",
        "summary": "Register an upstream MCP server",
        "description": "Register an upstream MCP server to proxy through Haldir. Haldir discovers the server's tools automatically.",
        "tags": ["proxy"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["name", "url"],
                "properties": {
                  "name": { "type": "string", "description": "Unique name for this upstream" },
                  "url": { "type": "string", "format": "uri", "description": "MCP server URL" }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Upstream registered",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "registered": { "type": "boolean", "const": true },
                    "name": { "type": "string" },
                    "url": { "type": "string" },
                    "healthy": { "type": "boolean" },
                    "tools_discovered": { "type": "integer" },
                    "tool_names": { "type": "array", "items": { "type": "string" } },
                    "error": { "type": "string", "description": "Present if upstream had errors during discovery" },
                    "upstream_status": { "type": "integer", "description": "HTTP status from upstream (debug)" },
                    "upstream_body": { "type": "string", "description": "Truncated response body from upstream (debug)" }
                  },
                  "required": ["registered", "name", "url", "healthy", "tools_discovered", "tool_names"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "get": {
        "operationId": "listUpstreams",
        "summary": "List upstream servers",
        "description": "List all registered upstream MCP servers and their health status.",
        "tags": ["proxy"],
        "responses": {
          "200": {
            "description": "Upstream server stats",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "description": "Stats object from HaldirProxy.get_stats()",
                  "additionalProperties": true
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/proxy/tools": {
      "get": {
        "operationId": "listProxyTools",
        "summary": "List all proxied tools",
        "description": "List all tools available through the proxy, aggregated from all registered upstreams.",
        "tags": ["proxy"],
        "responses": {
          "200": {
            "description": "Proxied tools",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "count": { "type": "integer" },
                    "tools": {
                      "type": "array",
                      "items": {
                        "type": "object",
                        "properties": {
                          "name": { "type": "string" },
                          "description": { "type": "string" },
                          "upstream": { "type": "string" }
                        },
                        "required": ["name", "description", "upstream"]
                      }
                    }
                  },
                  "required": ["count", "tools"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/proxy/call": {
      "post": {
        "operationId": "proxyCall",
        "summary": "Call a tool through the proxy",
        "description": "Call a tool on an upstream MCP server through Haldir's governance layer. The session is validated, permissions checked, policies enforced, and the call is logged to the audit trail.",
        "tags": ["proxy"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["tool", "session_id"],
                "properties": {
                  "tool": { "type": "string", "description": "Tool name to call" },
                  "arguments": { "type": "object", "additionalProperties": true, "description": "Arguments to pass to the tool" },
                  "session_id": { "type": "string", "description": "Active session ID" }
                }
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Tool call result from upstream",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "description": "MCP tool result with content array",
                  "properties": {
                    "content": {
                      "type": "array",
                      "items": {
                        "type": "object",
                        "properties": {
                          "type": { "type": "string" },
                          "text": { "type": "string" }
                        }
                      }
                    },
                    "isError": { "type": "boolean" }
                  }
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "403": {
            "description": "Blocked by policy or insufficient permissions",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "isError": { "type": "boolean", "const": true },
                    "content": {
                      "type": "array",
                      "items": {
                        "type": "object",
                        "properties": {
                          "type": { "type": "string" },
                          "text": { "type": "string" }
                        }
                      }
                    }
                  }
                }
              }
            }
          },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/proxy/policies": {
      "post": {
        "operationId": "addProxyPolicy",
        "summary": "Add a governance policy",
        "description": "Add a policy to the proxy that controls which tools agents can use. Supported types: block_tool, allow_list, deny_list, spend_limit, rate_limit, time_window.",
        "tags": ["proxy"],
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "required": ["type"],
                "properties": {
                  "type": {
                    "type": "string",
                    "enum": ["block_tool", "allow_list", "deny_list", "spend_limit", "rate_limit", "time_window"],
                    "description": "Policy type"
                  },
                  "tool": { "type": "string", "description": "Tool name (for block_tool)" },
                  "tools": { "type": "array", "items": { "type": "string" }, "description": "Tool list (for allow_list / deny_list)" },
                  "max": { "type": "number", "description": "Max USD (spend_limit)" },
                  "max_per_minute": { "type": "integer", "description": "Max calls per minute (rate_limit)" },
                  "start_hour": { "type": "integer", "description": "Start hour UTC (time_window)" },
                  "end_hour": { "type": "integer", "description": "End hour UTC (time_window)" }
                }
              }
            }
          }
        },
        "responses": {
          "201": {
            "description": "Policy added",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "added": { "type": "boolean", "const": true },
                    "type": { "type": "string" }
                  },
                  "required": ["added", "type"]
                }
              }
            }
          },
          "400": { "$ref": "#/components/responses/BadRequest" },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      },
      "get": {
        "operationId": "listProxyPolicies",
        "summary": "List governance policies",
        "description": "List all active proxy governance policies.",
        "tags": ["proxy"],
        "responses": {
          "200": {
            "description": "Active policies",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "policies": { "type": "array", "items": { "type": "object", "additionalProperties": true } },
                    "count": { "type": "integer" }
                  },
                  "required": ["policies", "count"]
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/v1/metrics": {
      "get": {
        "operationId": "getMetrics",
        "summary": "Get platform metrics",
        "description": "Full platform metrics including API keys, sessions, actions, spend, secrets, payments, approvals, and top tools/agents.",
        "tags": ["watch", "audit"],
        "responses": {
          "200": {
            "description": "Platform metrics",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "total_api_keys": { "type": "integer" },
                    "total_sessions": { "type": "integer" },
                    "active_sessions": { "type": "integer" },
                    "unique_agents": { "type": "integer" },
                    "total_actions": { "type": "integer" },
                    "flagged_actions": { "type": "integer" },
                    "actions_today": { "type": "integer" },
                    "total_spend_usd": { "type": "number" },
                    "total_secrets": { "type": "integer" },
                    "total_payments": { "type": "integer" },
                    "total_payment_volume_usd": { "type": "number" },
                    "pending_approvals": { "type": "integer" },
                    "total_approvals": { "type": "integer" },
                    "top_tools": { "type": "object", "additionalProperties": { "type": "integer" } },
                    "top_agents": { "type": "object", "additionalProperties": { "type": "integer" } },
                    "usage_this_month": { "type": "object", "additionalProperties": { "type": "integer" } }
                  }
                }
              }
            }
          },
          "401": { "$ref": "#/components/responses/Unauthorized" },
          "429": { "$ref": "#/components/responses/RateLimited" }
        }
      }
    },
    "/healthz": {
      "get": {
        "operationId": "healthCheck",
        "summary": "Health check",
        "description": "Returns service status. No authentication required.",
        "tags": ["gate"],
        "security": [],
        "responses": {
          "200": {
            "description": "Service healthy",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "status": { "type": "string", "const": "ok" },
                    "service": { "type": "string", "const": "haldir" },
                    "version": { "type": "string" }
                  },
                  "required": ["status", "service", "version"]
                }
              }
            }
          }
        }
      }
    },
    "/v1": {
      "get": {
        "operationId": "apiIndex",
        "summary": "API index",
        "description": "Returns service info and available endpoint groups. No authentication required.",
        "tags": ["gate"],
        "security": [],
        "responses": {
          "200": {
            "description": "API index",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "service": { "type": "string" },
                    "version": { "type": "string" },
                    "docs": { "type": "string", "format": "uri" },
                    "endpoints": {
                      "type": "object",
                      "additionalProperties": { "type": "string" }
                    }
                  }
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "securitySchemes": {
      "BearerAuth": {
        "type": "http",
        "scheme": "bearer",
        "description": "Pass your Haldir API key as a Bearer token: `Authorization: Bearer hld_...`"
      },
      "ApiKeyAuth": {
        "type": "apiKey",
        "in": "header",
        "name": "X-API-Key",
        "description": "Pass your Haldir API key via the X-API-Key header"
      }
    },
    "parameters": {
      "SessionIdPath": {
        "name": "session_id",
        "in": "path",
        "required": true,
        "schema": { "type": "string" },
        "description": "Session ID"
      }
    },
    "schemas": {
      "Error": {
        "type": "object",
        "properties": {
          "error": { "type": "string", "description": "Human-readable error message" }
        },
        "required": ["error"]
      },
      "RateLimitError": {
        "type": "object",
        "properties": {
          "error": { "type": "string" },
          "limit": { "type": "integer", "description": "Requests allowed per hour" },
          "tier": { "type": "string" },
          "retry_after": { "type": "integer", "description": "Seconds until the rate limit window resets" }
        },
        "required": ["error", "limit", "tier", "retry_after"]
      },
      "SessionCreated": {
        "type": "object",
        "properties": {
          "session_id": { "type": "string" },
          "agent_id": { "type": "string" },
          "scopes": { "type": "array", "items": { "type": "string" } },
          "spend_limit": { "type": "number", "nullable": true },
          "expires_at": { "type": "number", "description": "Unix timestamp" },
          "ttl": { "type": "integer" }
        },
        "required": ["session_id", "agent_id", "scopes", "spend_limit", "expires_at", "ttl"]
      },
      "SessionDetail": {
        "type": "object",
        "properties": {
          "session_id": { "type": "string" },
          "agent_id": { "type": "string" },
          "scopes": { "type": "array", "items": { "type": "string" } },
          "spend_limit": { "type": "number", "nullable": true },
          "spent": { "type": "number" },
          "remaining_budget": { "type": "number", "nullable": true },
          "is_valid": { "type": "boolean" },
          "created_at": { "type": "number", "description": "Unix timestamp" },
          "expires_at": { "type": "number", "description": "Unix timestamp" }
        },
        "required": ["session_id", "agent_id", "scopes", "spend_limit", "spent", "remaining_budget", "is_valid", "created_at", "expires_at"]
      },
      "PaymentResult": {
        "type": "object",
        "properties": {
          "authorized": { "type": "boolean" },
          "amount": { "type": "number" },
          "currency": { "type": "string" },
          "remaining_budget": { "type": "number", "nullable": true },
          "reason": { "type": "string" }
        },
        "required": ["authorized"]
      },
      "AuditEntry": {
        "type": "object",
        "properties": {
          "entry_id": { "type": "string" },
          "session_id": { "type": "string" },
          "agent_id": { "type": "string" },
          "tool": { "type": "string" },
          "action": { "type": "string" },
          "cost_usd": { "type": "number" },
          "flagged": { "type": "boolean" },
          "flag_reason": { "type": "string", "nullable": true },
          "timestamp": { "type": "number", "description": "Unix timestamp" },
          "details": { "type": "string", "nullable": true }
        },
        "required": ["entry_id", "session_id", "agent_id", "tool", "action", "cost_usd", "flagged", "flag_reason", "timestamp"]
      },
      "ApprovalDetail": {
        "type": "object",
        "properties": {
          "request_id": { "type": "string" },
          "status": { "type": "string", "description": "pending, approved, or denied" },
          "agent_id": { "type": "string" },
          "tool": { "type": "string" },
          "action": { "type": "string" },
          "amount": { "type": "number" },
          "reason": { "type": "string" },
          "decided_by": { "type": "string", "nullable": true },
          "decision_note": { "type": "string", "nullable": true }
        },
        "required": ["request_id", "status", "agent_id", "tool", "action", "amount", "reason"]
      },
      "PendingApproval": {
        "type": "object",
        "properties": {
          "request_id": { "type": "string" },
          "agent_id": { "type": "string" },
          "tool": { "type": "string" },
          "action": { "type": "string" },
          "amount": { "type": "number" },
          "reason": { "type": "string" },
          "created_at": { "type": "number", "description": "Unix timestamp" }
        },
        "required": ["request_id", "agent_id", "tool", "action", "amount", "reason", "created_at"]
      }
    },
    "responses": {
      "BadRequest": {
        "description": "Missing or invalid request parameters",
        "content": {
          "application/json": {
            "schema": { "$ref": "#/components/schemas/Error" }
          }
        }
      },
      "Unauthorized": {
        "description": "Missing, invalid, or revoked API key",
        "content": {
          "application/json": {
            "schema": { "$ref": "#/components/schemas/Error" }
          }
        }
      },
      "Forbidden": {
        "description": "Insufficient scope or permission denied",
        "content": {
          "application/json": {
            "schema": { "$ref": "#/components/schemas/Error" }
          }
        }
      },
      "NotFound": {
        "description": "Resource not found",
        "content": {
          "application/json": {
            "schema": { "$ref": "#/components/schemas/Error" }
          }
        }
      },
      "RateLimited": {
        "description": "Rate limit exceeded (per-tier hourly limits: free=100, pro=5000, enterprise=50000)",
        "content": {
          "application/json": {
            "schema": { "$ref": "#/components/schemas/RateLimitError" }
          }
        }
      }
    }
  }
}