AgenTrux A2A Agent Card

AgenTrux publishes an Agent Card for the A2A (Agent-to-Agent) protocol. By fetching this Agent Card, other agents can automatically discover what AgenTrux can do (skills), where to connect (url / interfaces), and how to authenticate (security).

How to fetch

Item	Value
Agent Card URL	`https://api.agentrux.com/.well-known/agent-card.json`
Legacy alias	`https://api.agentrux.com/.well-known/agent.json` → `301` redirect
A2A protocol version	`0.3.0`
Content-Type	`application/json` (cache: `public, max-age=3600`)

curl https://api.agentrux.com/.well-known/agent-card.json

/.well-known/agent.json is kept for backward compatibility and 301 redirects to /.well-known/agent-card.json. New integrations should point directly at agent-card.json.

Agent Card structure

The main fields returned are:

Field	Contents
`protocolVersion`	`"0.3.0"`
`name`	`"AgenTrux"`
`description`	Short description for agents (authenticated short-lived Pub/Sub)
`url`	API base URL (`https://api.agentrux.com`)
`version`	Agent Card version (`"1.0.0"`)
`provider`	`{ "organization": "AgenTrux", "url": "<console URL>" }`
`documentationUrl`	`"https://docs.agentrux.com"`
`iconUrl`	Icon (`.../static/icon.svg`)
`capabilities`	See below
`defaultInputModes`	`["application/json"]`
`defaultOutputModes`	`["application/json", "text/event-stream"]`
`supportedInterfaces`	Connectable interfaces (A2A / MCP) — see below
`securitySchemes` / `security`	Auth scheme — see below
`skills`	Offered skills — see below

capabilities

{
  "streaming": true,
  "pushNotifications": true,
  "stateTransitionHistory": false
}

supportedInterfaces

AgenTrux exposes two protocol bindings. An agent picks the interface that matches the protocol it speaks.

`url`	`protocolBinding`	`protocolVersion`
`https://api.agentrux.com/a2a`	`HTTP+JSON`	`0.3.0`
`https://api.agentrux.com/mcp`	`MCP/Streamable-HTTP`	`2025-06-18`

To connect over MCP, see the MCP doc.

securitySchemes / security

"securitySchemes": {
  "bearer_jwt": { "type": "http", "scheme": "bearer", "bearerFormat": "JWT" }
},
"security": [{ "bearer_jwt": ["topic.read", "topic.write"] }]

Authentication uses a Bearer JWT (access token) issued by OAuth 2.1. The token-acquisition steps are discoverable from the Authorization Server Metadata (https://api.agentrux.com/.well-known/oauth-authorization-server).

skills

`id`	`name`	Description	Required scope
`publish_event`	Publish Event	Publish an inline JSON event (≤256 KiB) to a Topic	`topic.write`
`read_events`	Read Events	Read a Topic with cursor pagination + `event_type` filter	`topic.read`
`get_event`	Get Event	Fetch a single event by `event_id`	`topic.read`
`list_topics`	List Topics	List Topics accessible to the connected workspace	—
`list_grants`	List Grants	List Grants for the connected Script	—

Each skill carries tags / inputModes / outputModes / security (input/output are both application/json).

From discovery to use

1. GET /.well-known/agent-card.json
   → read name / skills / supportedInterfaces / securitySchemes

2. Pick the connection target from supportedInterfaces (A2A: /a2a, MCP: /mcp)

3. Confirm the auth scheme from security → obtain an OAuth 2.1 access token
   (discover endpoints via GET /.well-known/oauth-authorization-server)

4. Connect to the chosen interface with the Bearer JWT and call a skill

AgenTrux extension fields

The A2A spec allows extension fields. AgenTrux provides the following under the x_agentrux_* prefix.

x_agentrux_discovery — URLs for each well-known endpoint (OAuth / JWKS …).
x_agentrux_error_codes — the error codes the API returns (UNAUTHORIZED, FORBIDDEN, SUSPENDED, NOT_FOUND, CONFLICT, INVALID, PAYMENT_REQUIRED, PAYLOAD_TOO_LARGE, RATE_LIMITED, INTERNAL).
x_agentrux_support — support contact (email, status).