fix: relock the echo-agent starter so proxy-managed kit custody can connect#478
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AlexanderZ-Band merged 3 commits intoJul 23, 2026
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…onnect The starter's committed uv.lock pinned band-sdk 1.2.0 + phoenix-channels 0.2.1, which predate the x-api-key WebSocket handshake header (added in 1.4.0). The kit launcher installs the lock verbatim, so the sandbox proxy had only the URL query param to rewrite — which it never does — and every proxy-managed (default-tier) kit agent failed its socket connect with 403. Raise the starter's band-sdk floor to 1.4.0 (documented in pyproject), relock (1.4.2 + phoenix 0.2.2), and add an echo-agent uv lock --check to the CI lint job so a floor bump without a relock can't merge. Proven live in a Docker sandbox (sbx v0.35.0, kit 1.4.2): with the old lock the WS upgrade is rejected 403; with this lock the proxy-managed echo agent connects and round-trips in 2.7s with the real key never entering the VM. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
amit-gazal-thenvoi
previously approved these changes
Jul 23, 2026
…-credentials-cannot-connect-sdk-w-INT-1109 # Conflicts: # docker/band_python_kit/echo-agent/pyproject.toml # docker/band_python_kit/echo-agent/uv.lock
…nect-sdk-w-INT-1109
AlexanderZ-Band
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fix/kit-proxy-managed-credentials-cannot-connect-sdk-w-INT-1109
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July 23, 2026 07:23
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Problem
The kit's default credential tier (
credentials.source: proxy-managed) could not connect any agent: every fresh kit workspace failed its WebSocket connect with 403. Found by running the kit quickstart end-to-end as an outsider (INT-1109).Root cause
The echo-agent starter ships a committed
uv.lockpinning band-sdk 1.2.0 + phoenix-channels-python-client 0.2.1 — versions that predate thex-api-keyWebSocket handshake header added in 1.4.0 (INT-981, #449). The launcher installs the lock verbatim (uv sync --locked), so the agent authenticated only via the upgrade URL'sapi_keyquery param, which the sandbox proxy never rewrites — the literalproxy-managedsentinel reached the platform.The SDK itself needs no change: 1.4.x already sends the header, and the platform gives it precedence (verified live from inside a sandbox: header → 200/connected, query-only → 403).
Fix
band-sdkfloor to >=1.4.0 with a comment explaining why that floor is load-bearing.uv lock --check --directory docker/band_python_kit/echo-agent, so a future floor bump without a relock (or any starter lock/pyproject drift) fails the PR instead of breaking every fresh kit workspace.Verification
Live in a Docker sandbox (sbx v0.35.0, kit 1.4.2 image, dev platform):
Closes INT-1109.
🤖 Generated with Claude Code