A2A AgentCard Export

The A2A AgentCard export is a public-discovery surface that projects a Mnemom-composed canonical alignment card into the A2A AgentCard v1.x envelope. The endpoint is unauthenticated: any consumer can fetch it; per-agent opt-in keeps the surface explicit. The export is one-way. Mnemom doesn’t accept inbound A2A registration in v1; that’s deferred to a future phase. The export pattern is the standard “publish for discovery” half of A2A.

Endpoint

GET /v1/agents/{agent_id}/a2a-agent-card

Property	Value
Auth	None — public surface
Per-agent gate	`agents.a2a_export_enabled` — when false, the endpoint returns 404 (not 403) to avoid leaking which agents exist on the platform
Caching	`Cache-Control: public, max-age=60, stale-while-revalidate=300`
ETag	`"sha256:<canonical content_hash>"` — clients can issue `If-None-Match` for cheap revalidation
CORS	`*` — the endpoint is intentionally cross-origin

What the projection includes

{
  "schemaVersion": "1.0",
  "name": "support-agent",
  "description": "Mnemom-composed alignment card declaring deliberation_before_action, policy_attentiveness, evidence_grounded.",
  "url": "https://api.mnemom.ai/v1/agents/smolt-e2ca60ef",
  "version": "1.17.0",
  "capabilities": { "streaming": false, "pushNotifications": false },
  "skills": [
    { "id": "campfire_create_chart_account", "name": "campfire_create_chart_account" }
  ],
  "extensions": [
    {
      "uri": "https://aap.mnemom.ai/v1/attestation",
      "required": false,
      "body": {
        "token": "<jws-compact>",
        "jwks_uri": "https://api.mnemom.ai/v1/.well-known/jwks.json"
      }
    },
    {
      "uri": "https://aap.mnemom.ai/v1/alignment",
      "required": false,
      "body": { "autonomy_mode": "observe", "values": { "declared": [...] }, "principal": {...} }
    }
  ],
  "metadata": {
    "content_hash": "<sha256-hex>",
    "composed_at": "2026-05-22T12:00:00Z"
  }
}

The extensions[].uri values above are namespace identifiers, not fetchable endpoints — aap.mnemom.ai does not resolve to a live host. A2A’s extension mechanism uses uri the way XML uses a namespace URI: a stable string that names the extension, not a URL you GET. To actually fetch the JWKS or the attestation body, use the jwks_uri and token fields inside the extension’s body, or the documented endpoints linked above.

Field	Source
`name`	`principal.identifier` from the alignment card; falls back to `agent_id`
`description`	Care-framed summary of the first six declared values
`version`	`1.<canonical version>.0` (semver shape)
`skills`	First 50 entries of `autonomy.bounded_actions`
`extensions[aap/attestation]`	Present when `AAP_ATTESTATION_SIGNING_ENABLED=true`; soft-omits on signing error
`extensions[aap/alignment]`	Public-safe subset of the canonical card

What the projection deliberately excludes

The public-discovery surface filters operator-internal fields:

card_id (smolt-internal)
_composition.source_card_id / _composition.source_policy_id
field_provenance (caller-aware redaction is server-side; A2A consumers don’t get a redacted view, they get no view)
Internal connector grants beyond the bare tool name surface

If you’d benefit from the full composed view including provenance, use GET /v1/agents/{id}/state under an authenticated principal.

Opt-in

Agents default to opted out (agents.a2a_export_enabled defaults to false) so no agent’s alignment posture is exposed on the public surface without an explicit decision. There is currently no self-serve API or dashboard toggle for this flag — if you want an agent’s AgentCard published for A2A discovery, contact Mnemom support to have it enabled. Once enabled, the AgentCard is live immediately (the per-request flag check happens on every fetch), and disabling it again returns the endpoint to 404 immediately.

Verifying the embedded attestation

Any A2A consumer can extract the extensions[aap/attestation].body.token and verify it offline against the published JWKS. The mnemom verify-card CLI does this for you in one command:

mnemom verify-card smolt-e2ca60ef

For programmatic verification, the wire format is documented; any JOSE/JWT library that supports EdDSA can verify.

Overview

Identity & Cards

Posture & Policy

Detection & Safe House

AEGIS

Reputation & Risk

Lifecycle

Gateway

Pricing

Policy

Specifications

Changelog

Endpoint

What the projection includes

What the projection deliberately excludes

Opt-in

Verifying the embedded attestation

See also

​Endpoint

​What the projection includes

​What the projection deliberately excludes

​Opt-in

​Verifying the embedded attestation

​See also

Endpoint

What the projection includes

What the projection deliberately excludes

Opt-in

Verifying the embedded attestation

See also