Bind consent round-trips to request data via a stable key - #20
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The MCP consent round-trip armed/confirmed on a key built inline in
session.ts as `consent:${pattern}:${op}:${JSON.stringify(data)}`. Two gaps:
the construction had no tested home (an edit to it was invisible to the
suite), and JSON.stringify is property-order sensitive — an agent re-issuing
the identical call with reconstructed data in a different key order would arm
a fresh round-trip instead of confirming, and a benign arming could be
redeemed by a differently-ordered call that happens to match.
Extract `consentKey(pattern, op, data)` into mutate-gate.ts (the pure
consent-decision home) and serialize data with sorted keys at every nesting
level (`stableStringify`), so semantically-identical re-issues confirm
regardless of property order. consent-key.test.ts locks the binding: the key
depends on pattern, operation, and data, and is order-insensitive at the top
level and nested.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BaKTAGEWWToMvX3xzgHFZC
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What
The MCP consent round-trip armed/confirmed on a key built inline in
session.tsasconsent:${pattern}:${op}:${JSON.stringify(data)}. Two gaps:JSON.stringifyis insertion-order dependent. An agent re-issuing the identical call with data reconstructed in a different key order would arm a fresh round-trip instead of confirming; separately, a benign arming could be redeemed by a differently-ordered call that happens to serialize to the same string.Change
consentKey(pattern, op, data)intomutate-gate.ts(the pure consent-decision home, alongsidemutateGate/findGatedBatchOp).stableStringify), so semantically-identical re-issues confirm regardless of property order.consent-key.test.tslocks the binding: the key depends on pattern, operation, and data, and is order-insensitive at the top level and nested.Provenance
Surfaced by a max-effort
/code-reviewof the working tree (the consentKey ordering bug was the one security-relevant finding across 11 finder angles). This is the review→ratchet loop: review caught it, the property test makes it durable.🤖 Generated with Claude Code