fix(a2a): wire AgentRegistry into --connect and fix JWS canonicalization - #6209
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AgentRegistry had no runtime construction site anywhere outside crates/zeph-a2a's own tests, so card_trust_policy enforced nothing on a running agent. Wire AgentRegistry::discover into `zeph --connect <URL>`, the only outbound A2A client path in the codebase, converting zeph-config's CardTrustPolicy/TrustedAgentKey to zeph-a2a's types via an explicit non-wildcard mapping and hardening the discovery fetch with the same TLS/SSRF posture already applied to the A2aClient connection. Discovery-fetch failure only aborts the connection under the "require" policy; under "ignore"/"prefer" it is tolerated so card-less peers keep connecting as before. Also fix canonical_payload to strip proto3-default-valued fields before JCS canonicalization, matching the A2A spec text, so a signature computed by a signer that strips defaults still verifies against a card transmitted with defaults present. Closes #6200 Closes #6201
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July 13, 2026 03:46
The doc comment referenced CardTrustPolicy::Require without the zeph_a2a:: qualifier the type needs to resolve outside its defining crate, since the bare name isn't imported into this module's scope. Add the missing reference-style link, matching the two link definitions already used for A2aError's variants right below it.
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Summary
Two follow-up fixes to the A2A Agent Card JWS signature verification + trust policy feature (#5928, PR #6202):
AgentRegistryhad no runtime construction site anywhere outsidecrates/zeph-a2a's own tests, so[a2a_client].card_trust_policyenforced nothing on a running agent. WiredAgentRegistry::discoverintozeph --connect <URL>(src/tui_remote.rs) — the only outbound A2A client path in the codebase — using an explicit non-wildcard conversion betweenzeph-configandzeph-a2a'sCardTrustPolicy/key types, and hardening the discovery fetch with the same TLS/SSRF posture already applied to theA2aClientconnection. Also fixes a real bug where the discovery URL was built from the full--connecttarget (including its RPC path) instead of the origin root where/.well-known/agent.jsonis served.card_signing::canonical_payloadcanonicalized the raw received card JSON verbatim, which would reject a genuinely valid card from a signer that strips proto3-default-valued fields before signing, per the A2A spec text. Fixed by stripping the same proto3-default fields recursively before JCS canonicalization, covered by a synthetic regression test (reala2a-sdkinterop is still unvalidated;card_trust_policyremains"ignore"by default pending a real signed-card vector).An adversarial critique round caught a real backward-compat regression in the initial wiring (discovery-fetch failure was unconditionally fatal to
--connect, breaking card-less peers under the defaultignorepolicy) — fixed by gating fatality on the trust policy so onlyrequirehard-fails on a fetch/parse failure; trust-check rejections (untrusted signature, URL-origin mismatch) remain fatal under every policy.Closes #6200
Closes #6201
Test plan
cargo +nightly fmt --checkcargo clippy --profile ci --workspace --all-targets --features "desktop,ide,server,chat,pdf,scheduler,testing" -- -D warningscargo nextest run --config-file .github/nextest.toml --workspace --features "desktop,ide,server,chat,pdf,scheduler" --lib --bins(13357 passed, 0 failed)RUSTFLAGS="-D warnings" RUSTDOCFLAGS="--deny rustdoc::broken_intra_doc_links" cargo doc --no-deps --workspace --features "desktop,ide,server,chat,pdf,scheduler"cargo test --doc -p zeph-a2a -p zeph-config --all-featuresCHANGELOG.md,specs/014-a2a/spec.md,.local/testing/playbooks/a2a.md,.local/testing/coverage-status.md--connectpath against a real signed/unsigned peer (flagged in the playbook as the next live-tester cycle's priority target)