---
title: "The gateway's self-published DID document."
method: GET
path: "/.well-known/did.json"
tags: ["Identity"]
---

# The gateway's self-published DID document.

`GET /.well-known/did.json`

## Request

- Base URL: `http://localhost:3774`
- URL: `http://localhost:3774/.well-known/did.json`
- Auth: none required
- TypeScript: <https://skmtc.dev/getbindu/apis/bindu-gateway-api/docs/.well-known/did.json/get.ts> (a function with typed inputs; its response is checked against the schema)

Returns a W3C DID Core v1-compatible document with the gateway's
Ed25519 public key under `authentication[]`. A2A peers that
accept `did_signed` requests fetch this to verify the gateway's
outbound signatures.

**Availability:** only registered when the gateway has a DID
identity configured via env — `BINDU_GATEWAY_DID_SEED`,
`BINDU_GATEWAY_AUTHOR`, and `BINDU_GATEWAY_NAME` all set. When no
identity is loaded this endpoint returns 404.

**Caching:** the gateway's DID is stable across process lifetime
(env-driven); responses carry `Cache-Control: public, max-age=300`
as a defense against bad caches that would otherwise hold the key
indefinitely.

**Content-Type:** `application/did+json` per W3C DID Core, not
plain `application/json`. Some DID resolvers enforce the media
type.

**Auth:** none. Well-known endpoints are public by spec — the
whole point is that any peer can resolve the DID without
credentials.

## Response `200`

DID document for the configured gateway identity.

- GatewayDidDocument: W3C DID Core v1 document describing the gateway's identity. Deliberately omits `created` — the gateway's identity is env- driven and stateless, so there's no persisted "first published" moment to report (W3C DID Core has `created` as optional).
  - `@context` string[], required
  - `id` string, required
  - `authentication` GatewayVerificationMethod[], required
    - `id` string, required
    - `type` 'Ed25519VerificationKey2020', required
    - `controller` string, required
    - `publicKeyBase58` string, required: Ed25519 public key, base58-encoded.

## Other responses

- `404`: No DID identity configured on this gateway instance.

---

[API](https://skmtc.dev/getbindu/apis/bindu-gateway-api.md) - [All operations](https://skmtc.dev/getbindu/apis/bindu-gateway-api/llms.txt) - [OpenAPI document](https://skmtc.dev/getbindu/apis/bindu-gateway-api/revisions/3c89680038fb?raw)