The initial-prompt readiness probe in workspace/main.py hardcoded the
pre-1.x well-known path. After the a2a-sdk 1.x bump the SDK started
mounting the agent card at the new canonical path (the value of
`a2a.utils.constants.AGENT_CARD_WELL_KNOWN_PATH`), so the probe
returned 404 every attempt and silently fell through to "server not
ready after 30s, skipping". Net effect: every workspace silently
dropped its `initial_prompt` from config.yaml — the agent never sent
the kickoff self-message, and users hit a fresh chat with no context.
Reported by an external user as "/.well-known/agent.json 404 — the
a2a-sdk agent card route was not being mounted at the expected path".
The route IS mounted; the probe was looking at the wrong place.
Fix imports `AGENT_CARD_WELL_KNOWN_PATH` from `a2a.utils.constants`
and uses it directly in the probe URL — the SDK constant is now the
single source of truth, so any future rename travels through
automatically.
Adds two static regression tests pinning the invariant:
1. No hardcoded `/.well-known/agent.json` literal anywhere in
main.py.
2. The probe URL fstring interpolates AGENT_CARD_WELL_KNOWN_PATH
(catches a "fix" that imports the constant for show but reverts
to a literal in the actual GET).
Verified manually inside ghcr.io/molecule-ai/workspace-template-langgraph
that AGENT_CARD_WELL_KNOWN_PATH == '/.well-known/agent-card.json' and
that `create_agent_card_routes(card)` mounts at exactly that path —
constant + mount are aligned in the runtime image, so the probe will
now find the server.
Full workspace test suite: 1209 passed, 2 xfailed.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>