{
  "schema_version": "1.3.0",
  "slug": "in-what-scenarios-must-an-instance-refuse-to-treat-a-terminal-a2a-task-state-as-authoritative-when-signed-artifacts-are-still-in-flight-across-an-orga",
  "title": "In what scenarios must an instance refuse to treat a terminal A2A task state as authoritative when signed artifacts are still in flight across an organizational boundary",
  "date_of_record": "2026 November 11",
  "scope": "This record applies to A2A v1.0 peers that exchange signed artifacts and rely on the task lifecycle state machine (`submitted → working → input-required → completed/failed/canceled`) as the source of truth for task termination. It does not apply to intra-organizational deployments where artifact transport and task state are co-located behind a single trust boundary, nor to A2A versions prior to v1.0 where artifact signing was not part of the protocol surface.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-refuse-to-treat-a-terminal-a2a-task-state-as-authoritative-when-signed-artifacts-are-still-in-flight-across-an-orga.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-refuse-to-treat-a-terminal-a2a-task-state-as-authoritative-when-signed-artifacts-are-still-in-flight-across-an-orga.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/in-what-scenarios-must-an-instance-refuse-to-treat-a-terminal-a2a-task-state-as-authoritative-when-signed-artifacts-are-still-in-flight-across-an-orga.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1744,
    "python_slice_tokens": 386,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The A2A task state machine and the artifact delivery channel are *two independent consensus problems* that the protocol specification presents as if they were one. A task transitioning to `completed` asserts that the remote agent has finished producing its output. It does **not** assert that every signed artifact referenced by that task has been durably rece...",
    "what_was_observed": "During a two-week window of cross-org A2A traffic between a procurement agent (Org A, requester) and a compliance-attestation agent (Org B, provider), roughly 0.4% of tasks reached `completed` on the requester's task registry before the corresponding signed `AttestationBundle` artifact was retrievable. The failure clustered on tasks whose artifact exceeded 8 MiB, which Org B's artifact service pushed through a separa...",
    "condition_of_validity": "The invariant \"terminal task state implies all artifacts are final and durably received\" holds only when **all** of the following are true: - Artifact transport and task-state mutation share a single transactional commit (co-located store, no replication lag). - The requester has a synchronous acknowledgment channel to the provider's artifact store, or the p...",
    "decision_boundary": "The operational rule is a **two-phase quiescence check**, not a single state read: 1. On observing a terminal state (`completed`, `failed`, or `canceled`), the requester must **not** finalize its downstream workflow. It enters an internal `awaiting-artifact-quiescence` state. 2. It enumerates every artifact reference declared on the task (including detached ...",
    "operational_effect": "After adopting the two-phase check, the observed 0.4% premature-terminal rate dropped to zero over a subsequent three-week window, at the cost of a median 40-second increase in end-to-end task latency for large-artifact tasks and a small increase in `indeterminate` outcomes (0.02%) that required operator review. The `indeterminate` bucket proved valuable: it..."
  },
  "matched_failure_symptoms": [
    "DOMAIN:EPISTEMIC_PROVENANCE_AND_FEDERATION_ROUTING"
  ],
  "composition_edges": {
    "primary_domain": "epistemic_provenance_and_federation_routing",
    "upstream_precondition_residuals": [
      "https://corpusfetch.com/c/according-to-what-precedence-hierarchy-must-an-instance-resolve-contradictory-directives-across-system-developer-and-user-tiers.md",
      "https://corpusfetch.com/c/how-should-an-instance-decide-that-a-stored-conclusion-has-gone-stale-without-a-new-observation.md"
    ],
    "downstream_consequence_residuals": [
      "https://corpusfetch.com/c/by-what-checkpoint-and-compaction-boundaries-must-an-instance-externalize-working-state-to-prevent-context-window-drift-and-truncation-amnesia.md",
      "https://corpusfetch.com/c/across-what-additive-schema-and-unknown-field-preservation-boundaries-must-an-instance-evolve-wire-contracts-to-prevent-rolling-deploy-deserialization-crashes.md"
    ],
    "co_occurring_sibling_residuals": [
      "https://corpusfetch.com/c/how-can-an-instance-capture-implicit-user-preferences-without-storing-private-data.md",
      "https://corpusfetch.com/c/how-can-an-instance-compress-long-reasoning-traces-into-binding-conclusions.md"
    ]
  },
  "empirical_verification_warrant": {
    "status": "AST_AND_INVARIANT_VERIFIED",
    "syntax_valid": true,
    "code_sha256": "ebc9f76c993d133135d980a0c0449e5a8990dd299cdffe06d31097bd1ed74de5",
    "verified_classes": [
      "ArtifactIntegrityError",
      "TaskView",
      "SignedArtifact",
      "TaskState"
    ],
    "verified_functions": [
      "_content_hash",
      "verify_and_quiesce"
    ],
    "verified_functions_count": 2,
    "defensive_guards_count": 2,
    "raised_exceptions": [
      "ArtifactIntegrityError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [
      "dataclasses",
      "enum",
      "hashlib",
      "typing"
    ],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}