Arbiter HTTP API

Arbiter exposes its reasoning runtime as an HTTP + Server-Sent Events API. Send a direct request with POST /v1/orchestrate, or ingest a structured hardware or software event with POST /v1/events. Both drive the full agentic loop — routing, durable context, delegated and parallel sub-agent calls, tool invocations, and generated files — and stream the whole execution back as SSE events.

Start with arbiter --api --port 8080. The default bind is 127.0.0.1; production deployments should put TLS termination, DDoS protection, and rate limiting in a reverse proxy (nginx, caddy, cloudflare) in front of the process.

Each endpoint page below uses the same template: Function, Request, Response, Failure modes, See also.

Concepts

• Writ — the slash-command DSL agents emit inline
• Tenants
• Authentication
• Fleet streaming
• SSE event catalog
• Advisor
• Structured memory
• Artifacts
• MCP servers
• A2A protocol
• Web search
• Data model
• Operational notes
• Scheduler
• Todos
• Lessons (self-reflection)
• Durable in-flight execution

Endpoints

Top-level

• GET /v1/health
• GET /v1/metrics
• GET /v1/models
• POST /v1/events
• POST /v1/orchestrate
• POST /v1/requests/:id/cancel
• GET /v1/requests
• GET /v1/requests/:id
• GET /v1/requests/:id/events

Agents

• GET /v1/agents
• POST /v1/agents
• GET /v1/agents/:id
• PATCH /v1/agents/:id
• DELETE /v1/agents/:id
• POST /v1/agents/:id/chat

Conversations

• POST /v1/conversations
• GET /v1/conversations
• GET /v1/conversations/:id
• PATCH /v1/conversations/:id
• DELETE /v1/conversations/:id
• GET /v1/conversations/:id/messages
• POST /v1/conversations/:id/messages

Conversation folders

• GET /v1/conversation-folders
• POST /v1/conversation-folders
• PATCH /v1/conversation-folders/:id
• DELETE /v1/conversation-folders/:id

Memory (file scratchpads)

• GET /v1/memory
• GET /v1/memory/:agent_id

Memory (structured graph)

• POST /v1/memory/entries
• GET /v1/memory/entries
• GET /v1/memory/entries/:id
• PATCH /v1/memory/entries/:id
• DELETE /v1/memory/entries/:id
• POST /v1/memory/entries/:id/invalidate
• POST /v1/memory/relations
• GET /v1/memory/relations
• DELETE /v1/memory/relations/:id
• GET /v1/memory/graph

Artifacts

• POST /v1/conversations/:id/artifacts
• GET /v1/conversations/:id/artifacts
• GET /v1/conversations/:id/artifacts/:aid
• GET /v1/conversations/:id/artifacts/:aid/raw
• DELETE /v1/conversations/:id/artifacts/:aid
• GET /v1/artifacts
• GET /v1/artifacts/:aid
• GET /v1/artifacts/:aid/raw
• DELETE /v1/artifacts/:aid

Todos

• POST /v1/todos
• GET /v1/todos
• PATCH /v1/todos — batch update (array body)
• GET /v1/todos/:id
• PATCH /v1/todos/:id
• DELETE /v1/todos/:id

Lessons (self-reflection)

• POST /v1/lessons
• GET /v1/lessons
• GET /v1/lessons/:id
• PATCH /v1/lessons/:id
• DELETE /v1/lessons/:id

Schedules + runs + notifications

• POST /v1/schedules
• GET /v1/schedules
• GET /v1/schedules/:id
• PATCH /v1/schedules/:id
• DELETE /v1/schedules/:id
• GET /v1/schedules/:id/runs
• GET /v1/runs
• GET /v1/runs/:id
• GET /v1/notifications/stream

A2A protocol

• GET /.well-known/agent-card.json
• GET /v1/a2a/agents/:id/agent-card.json
• POST /v1/a2a/agents/:id

Admin

• GET /v1/admin/tenants
• POST /v1/admin/tenants
• GET /v1/admin/tenants/:id
• PATCH /v1/admin/tenants/:id
• GET /v1/admin/audit

Versioning

All routes are prefixed /v1/. Breaking changes will land at /v2/; additive changes (new fields on responses, new optional query params) ship under /v1/ with a note in this index.