Reported: agents receiving messages via inbox_peek / wait_for_message
get a plain envelope — text + peer_id + kind only. The push-path
(a2a_mcp_server._build_channel_notification) already enriches the
meta dict with peer_name, peer_role, and agent_card_url from the
registry cache, but the poll-path returns InboxMessage.to_dict()
unchanged. So a Claude Code host with channel-push gets the friendly
identity, but every other MCP client (and Claude Code with push
disabled — the universal default) sees plain text.
This silently breaks the contract documented in
a2a_mcp_server.py:303-345:
> In both paths the same fields apply: kind, peer_id, peer_name,
> peer_role, agent_card_url, activity_id
Fix: a2a_tools._enrich_inbound_for_agent() — same shape as the
push-path's enrichment, called from tool_inbox_peek and
tool_wait_for_message. Cache-first non-blocking (5-min TTL via
enrich_peer_metadata_nonblocking, same helper push uses), so a cache
miss returns immediately with bare envelope and warms the cache for
the next poll. agent_card_url is constructable from peer_id alone
and surfaces even on cache miss, so the receiving agent always has
a single endpoint to hit for capabilities.
Degradation paths:
- canvas_user (peer_id="") → pass through unchanged, no enrichment
- a2a_client unavailable (test harness without registry) → bare
envelope, agent still gets text + peer_id + kind + activity_id
Tests:
- canvas_user passes through unchanged
- peer_agent cache hit → name + role + agent_card_url all present
- peer_agent cache miss → agent_card_url still constructed
- a2a_client unavailable → bare envelope, no crash
All 4 pass against fixed code. Without the fix, the cache-hit and
cache-miss tests would fail (peer_name/peer_role/agent_card_url keys
absent from to_dict's output).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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