CRITICAL: every workspace boot since the a2a-sdk 1.0 migration (#1974)
has been crashing at AgentCard construction with:
ValueError: Protocol message AgentCard has no "supported_protocols" field
The protobuf field is `supported_interfaces` (plural, interfaces — see
a2a-sdk types/a2a_pb2.pyi:189). The 0.3→1.0 migration left the kwarg
as `supported_protocols`, which doesn't exist in the 1.0 schema, so
the constructor raises before any subsequent line of main runs.
Why this hid for so long:
- publish-runtime.yml's smoke step only IMPORTED molecule_runtime.main;
importing the module is fine, only CONSTRUCTING the AgentCard fails
- The user-visible symptom is "Workspace failed: " with empty
last_sample_error, indistinguishable from generic boot timeouts
- The state_transition_history=True bug (fixed in #2179) was a
sibling of this — same migration, same class, just caught first
Fix is symmetric with #2179:
1. workspace/main.py: rename the kwarg + comment explaining why
2. .github/workflows/publish-runtime.yml: extend the smoke block to
instantiate AgentCard with the exact production call shape, so
the next field-rename of this class fails at publish time
instead of breaking every workspace startup
Verification:
- Constructed AgentCard against fresh a2a-sdk 1.0.2 in a clean
venv with the corrected kwarg → succeeds
- Constructed it with the original `supported_protocols` kwarg →
fails immediately with the exact error production sees
- Smoke test pinned to mirror main.py's exact call shape; main.py
+ smoke must stay in lockstep going forward
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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