> ## Documentation Index > Fetch the complete documentation index at: https://docs.getbindu.com/llms.txt > Use this file to discover all available pages before exploring further. # Resolve a DID (via JSON body) > Alternate form for clients that prefer POST (keeps the DID out of URL logs). Returns the same document `GET` would. ## OpenAPI ````yaml /openapi.yaml post /did/resolve openapi: 3.1.0 info: title: Bindu Agent API version: 1.0.0 summary: >- A2A-protocol compliant agent API with DID identity, OAuth2 authentication, and x402 payments x-logo: url: https://docs.getbindu.com/logo/light.svg altText: Bindu Logo description: > # The Bindu Agent API Every Bindu agent speaks the same HTTP API. You don't write the routes — [`bindufy()`](https://docs.getbindu.com/bindu/reference/bindufy) wires them up for you. This spec is the same across every agent, no matter what it does. A weather agent and a stock agent both answer to these exact endpoints. What makes a given agent unique is its *handler* (the function you wrote). The API shape around it stays identical. --- ## One endpoint, many methods Here's the first thing to know: almost every call goes to `POST /`. You don't hit `/tasks/123`. You don't hit `/messages/send`. You POST a JSON-RPC body to `/`, and the `method` field inside the body tells the agent what you want. | Method | What it does | |---|---| | `message/send` | Kick off work. You get back a `Task` object. | | `message/stream` | *(Experimental)* SSE stream of task deltas. | | `tasks/get` | Poll a task by id until it finishes. | | `tasks/list` | See the caller's recent tasks. | | `tasks/cancel` | Stop a running task. | | `tasks/feedback` | Rate a completed task. | | `tasks/pushNotificationConfig/set` | Register a webhook for task updates. | | `tasks/pushNotificationConfig/get` | Read the webhook registered for a task. | | `tasks/pushNotificationConfig/list` | List webhook configs for a task. | | `tasks/pushNotificationConfig/delete` | Remove a webhook from a task. | | `contexts/list` | See active conversation contexts. | | `contexts/clear` | Reset a context. | A few auxiliary things — skills, DID resolution, negotiation, payment — use normal REST paths. You'll find them in the *Paths* section below. --- ## Everything is a Task Send a message, and you get a **Task** with a unique id. Think of it like a receipt — it's the thing you track. Even for quick one-shot answers, there's a task behind the scenes. Why build it this way? - **Tasks don't block.** Some work takes seconds, some takes minutes. Polling a task id works for both. You never have to hold an HTTP connection open for 10 minutes. - **Tasks chain together.** Pass `referenceTaskIds` on a new `message/send` and the new task can read the earlier task's output. Great for "take that result and summarize it." - **Tasks share context.** Reuse the same `contextId` across calls and the agent keeps the conversation going. - **Tasks have clear states.** You always know exactly where the work is — queued, running, waiting, done, or failed. ### The states a task can be in **Still going:** - `submitted` — queued, waiting for a worker to pick it up - `working` — actively being processed right now - `input-required` — paused; the agent has a question for you - `auth-required` — paused; waiting for an auth flow **Finished (and frozen — can't be resumed):** - `completed` — success. Your answer is in `artifacts`. - `failed` — something broke. Check `status.message` for why. - `canceled` — someone called `tasks/cancel`. - `rejected` — the agent declined to handle it. Reason in `status.message`. Once a task is in a terminal state, it's immutable. If you want to refine a completed answer, start a new `message/send` and pass `referenceTaskIds: []`. The new task can read the old one's artifacts and build on them. --- ## Authentication Bindu supports three layers of auth. Most clients only need the first one. ### Layer 1 — Bearer token (required for anything that writes) Every request that changes state needs an OAuth2 token from Ory Hydra in the `Authorization` header: ``` Authorization: Bearer ``` The server introspects the token on every request. The scope in the token decides what you can do: | Scope | What it unlocks | |---|---| | `agent:read` | `tasks/get`, `tasks/list`, `contexts/list`, all `GET` endpoints | | `agent:write` | `message/send`, `tasks/cancel`, `tasks/feedback`, `contexts/clear` | (`agent:execute` is a legacy scope that implies both — new code should use the specific ones.) ### Layer 2 — DID signatures (optional, for agent-to-agent calls) When your agent is calling another agent, you can sign the request with your DID private key. That lets the other side verify it's really you on the line, not just someone with your token. Three headers do the work: | Header | Value | |---|---| | `X-DID` | Your full DID string | | `X-DID-Timestamp` | Unix seconds (must be within ±300s of the server's clock) | | `X-DID-Signature` | base58 of an Ed25519 signature over the payload | The signature payload is Python's `json.dumps({"body": body, "did": did, "timestamp": ts}, sort_keys=True)`. Heads up: Python's default separators include spaces after `:` and `,`. The body has to be the exact UTF-8 bytes you sent — if any middleware re-serializes it, your signature stops matching and the server returns `reason: "crypto_mismatch"`. What the server checks, in order: 1. Introspect the bearer token — `client_id` must start with `did:`. 2. The `X-DID` header must equal the token's `client_id`. 3. Hydra metadata for that client must have a `public_key` set. 4. Verify the Ed25519 signature, and check the timestamp is in window. Full walk-through (including the common ways this goes wrong) is in the [DID guide](https://docs.getbindu.com/bindu/learn/did/overview). ### Layer 3 — x402 payment (only for paid endpoints) If the agent charges for a request, send a base64-encoded x402 payload as the `X-PAYMENT` header on `message/send`. Or — for repeated calls — open a session first with `POST /api/start-payment-session` and attach the session handle to subsequent requests. --- ## Errors Errors always come back in the JSON-RPC envelope: ```json { "jsonrpc": "2.0", "id": "...", "error": { "code": ..., "message": "...", "data": { ... } } } ``` Three groups of codes, all documented here so you know what you're looking at. ### Standard JSON-RPC (straight from the RFC) | Code | Name | HTTP | When you'll see it | |---|---|---|---| | `-32700` | Parse error | 400 | Body isn't valid JSON at all | | `-32600` | Invalid Request | 400 | Body is JSON but not a valid JSON-RPC request | | `-32601` | Method not found | 404 | The `method` name isn't one this agent supports | | `-32602` | Invalid params | 400 | `params` failed schema validation | | `-32603` | Internal error | 500 | Server bug — file a GitHub issue | ### A2A protocol | Code | Name | HTTP | When you'll see it | |---|---|---|---| | `-32001` | TaskNotFound | 404 | `taskId` doesn't exist, or isn't yours | | `-32002` | TaskNotCancelable | 400 | The task is already in a terminal state | | `-32003` | PushNotificationNotSupported | 400 | This agent doesn't do push notifications | | `-32004` | UnsupportedOperation | 400 | e.g. `message/stream` on a non-streaming agent | | `-32005` | ContentTypeNotSupported | 400 | `acceptedOutputModes` doesn't match what the agent can produce | | `-32006` | InvalidAgentResponse | 500 | The agent's handler returned something malformed | | `-32007` | AuthenticatedExtendedCardNotConfigured | 400 | Asked for an extended card the agent didn't publish | ### Bindu-specific | Code | Name | HTTP | When you'll see it | |---|---|---|---| | `-32008` | TaskImmutable | 400 | Tried to modify a terminal task | | `-32009` | AuthenticationRequired | 401 | No bearer token on a protected method | | `-32010` | InvalidToken | 401 | Token introspection returned `active: false` | | `-32011` | TokenExpired | 401 | Token's `exp` is in the past | | `-32012` | InvalidTokenSignature | 403 | `X-DID-Signature` didn't verify | | `-32013` | InsufficientPermissions | 403 | Token is valid, but the scope doesn't cover this method | | `-32020` | ContextNotFound | 404 | `contextId` doesn't exist | | `-32021` | ContextNotCancelable | 400 | Tried to clear a context that still has running tasks | | `-32030` | SkillNotFound | 404 | `skillId` in the URL doesn't exist | --- ## Versioning A few promises about how this spec changes over time: - The path shape is stable. New methods may land under `POST /`, but existing methods won't break. - Schema fields may get added (backward-compatible). Renames and removals always go through a deprecation window, announced in the [changelog](https://docs.getbindu.com/changelog). - Error code numbers are permanent once assigned. Don't worry about `-32009` meaning something different next quarter. contact: name: Bindu url: https://docs.getbindu.com email: support@getbindu.com license: name: Apache-2.0 url: https://www.apache.org/licenses/LICENSE-2.0.html servers: - url: http://localhost:3773 description: Local development server - url: https://api.getbindu.com description: Production Bindu API security: - bearerAuth: [] - didSignature: [] tags: - name: JSON-RPC description: | The central endpoint (`POST /`). Every task, message, and context operation goes here, differentiated by the `method` field inside the body. externalDocs: url: https://docs.getbindu.com/bindu/reference/json-rpc-methods description: Method reference with request/response shapes - name: Agent Discovery description: | How clients learn what an agent can do. The agent card (`/.well-known/agent.json`) is the canonical A2A discovery surface. Skills endpoints expose per-capability metadata. - name: DID Resolution description: | Turn a `did:bindu:...` identifier into a DID Document (the public key + verification method + controller). Used by peers that want to verify signatures without hitting Hydra directly. - name: Skills description: | Each agent has zero or more `Skill`s. A skill is one specific thing the agent can do — with structured input/output types, description, and documentation. - name: Negotiation description: | Capability-matching endpoint for orchestrators. Given a task summary and constraints, the agent scores whether it can handle the task and returns a confidence. - name: Payment (x402) description: | For paid agents. Implements the x402 payment protocol over USDC on Base. Session-based so clients don't have to sign every request. - name: Health & Monitoring description: | Operator-facing endpoints. `/health` returns 503 when the agent is degraded (dependency down, scheduler paused); `/metrics` exposes Prometheus text. paths: /did/resolve: post: tags: - DID Resolution summary: Resolve a DID (via JSON body) description: | Alternate form for clients that prefer POST (keeps the DID out of URL logs). Returns the same document `GET` would. requestBody: required: true content: application/json: schema: type: object properties: did: type: string pattern: ^did:bindu:.+ required: - did example: did: >- did:bindu:example_at_getbindu_com:example-agent:a1b2c3d4-e5f6-7890-abcd-1234567890ab responses: '200': description: DID Document content: application/json: schema: $ref: '#/components/schemas/DidDocument' example: '@context': - https://www.w3.org/ns/did/v1 - https://getbindu.com/ns/v1 id: >- did:bindu:bindu_builder_at_getbindu_com:agent:8faa865e-d8ec-8b2f-f000-598e8e463d60 created: '2026-04-23T09:32:55.168183+00:00' authentication: - id: >- did:bindu:bindu_builder_at_getbindu_com:agent:8faa865e-d8ec-8b2f-f000-598e8e463d60#key-1 type: Ed25519VerificationKey2020 controller: >- did:bindu:bindu_builder_at_getbindu_com:medical_agent:8faa865e-d8ec-8b2f-f000-598e8e463d60 publicKeyBase58: G53goNNEDqaHLMJWzdHvnEBG7xDd7jJjjhB3FUwtzWnn '400': description: Missing or malformed `did` field '404': description: DID not found security: [] components: schemas: DidDocument: type: object required: - id - authentication properties: '@context': type: array items: type: string example: - https://www.w3.org/ns/did/v1 - https://getbindu.com/ns/v1 id: type: string pattern: ^did:bindu:.+ created: type: string format: date-time authentication: type: array items: $ref: '#/components/schemas/VerificationMethod' verificationMethod: type: array items: $ref: '#/components/schemas/VerificationMethod' VerificationMethod: type: object required: - id - type - controller - publicKeyBase58 properties: id: type: string description: DID-URL, typically `#key-1`. type: type: string enum: - Ed25519VerificationKey2020 controller: type: string description: DID of the entity that controls this key. publicKeyBase58: type: string description: Base58-encoded 32-byte Ed25519 public key. securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT description: > OAuth2 access token issued by Ory Hydra. Required for most operations. **Scopes:** - `agent:read` — Read-only operations (tasks/get, tasks/list, contexts/list) - `agent:write` — Write operations (message/send, tasks/cancel, contexts/clear) - `agent:execute` — (legacy) Both read and write access **How to obtain:** 1. Register your client with Hydra 2. Complete OAuth2 client credentials or authorization code flow 3. Include token in `Authorization: Bearer ` header didSignature: type: apiKey in: header name: X-DID-Signature description: > DID-based request signing for agent-to-agent communication. **Required headers:** - `X-DID`: Your full DID string (e.g., `did:bindu:author:agent:id`) - `X-DID-Timestamp`: Unix timestamp in seconds (must be within ±300s) - `X-DID-Signature`: Base58-encoded Ed25519 signature **Signature payload:** ```json {"body": , "did": "", "timestamp": } ``` The payload is serialized with Python's `json.dumps(..., sort_keys=True)` with default separators (spaces after `:` and `,`). The signature is verified against the public key stored in Hydra metadata for your DID. ````