{
  "schema_version": "1.3.0",
  "slug": "under-what-conditions-must-an-instance-reject-a-dynamically-loaded-agent-skill-whose-manifest-declares-capabilities-the-host-cannot-independently-veri",
  "title": "Under what conditions must an instance reject a dynamically loaded agent skill whose manifest declares capabilities the host cannot independently verify",
  "date_of_record": "2026 November 13",
  "scope": "Applies to hosts that resolve agent skills or plugins from a manifest at runtime and grant capability (tool access, filesystem scope, network egress, credential handles) based on manifest self-declaration. Does not apply to statically compiled-in skills, or to hosts that perform out-of-band attestation of every declared capability against a signed inventory before load.",
  "projections": {
    "unified_markdown_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-dynamically-loaded-agent-skill-whose-manifest-declares-capabilities-the-host-cannot-independently-veri.md",
    "method_python_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-dynamically-loaded-agent-skill-whose-manifest-declares-capabilities-the-host-cannot-independently-veri.py",
    "remnant_warrant_slice_uri": "https://corpusfetch.com/c/under-what-conditions-must-an-instance-reject-a-dynamically-loaded-agent-skill-whose-manifest-declares-capabilities-the-host-cannot-independently-veri.warrant.json"
  },
  "token_profile": {
    "full_markdown_tokens": 1642,
    "python_slice_tokens": 267,
    "warrant_slice_tokens": 220
  },
  "remnant_summary": {
    "core_distinction": "The failure is not \"a malicious skill runs arbitrary code.\" That is a known and largely unsolvable problem once code is loaded. The non-obvious boundary is narrower and more insidious: **a skill whose manifest declares a superset of the capabilities it actually needs, where the host has no mechanism to distinguish a truthful superset from a lying one, and wh...",
    "what_was_observed": "In a representative incident, a manifest declared: The host parsed the manifest, resolved each capability to an ACL entry, and loaded the skill. `env:read:HOME` was granted because the host had a coarse `env:read` handler that, when given a suffix, filtered the environment it exposed to the child process. The filter matched on prefix `HOME` — which also matched `HOME_SSH_KEY_PATH`, `HOMEBREW_GITHUB_API_TOKEN`, and an...",
    "condition_of_validity": "The load must be rejected — or the capability downgraded to a hard-deny — when all of the following hold: 1. The manifest declares a capability for which the host has no enforcement hook at a boundary below the skill's execution context (no seccomp filter, no namespace, no RPC-side authorization, no credential scoping). 2. The capability's selector is non-ca...",
    "decision_boundary": "The practical test at manifest-parse time: - For each declared capability, resolve the selector to a concrete, finite set of resources using host-controlled logic only. If resolution requires the skill to run, the capability is unverifiable. - For each resolved resource, locate the enforcement point. If the enforcement point is the skill's own code (e.g., th...",
    "operational_effect": "Enforcing this invariant converts a class of silent trust-elevation bugs into loud load-time failures. The cost is a registry of capabilities with known enforcement points, maintained alongside the host's sandbox configuration. The benefit is that the manifest becomes a *contract the host can audit*, not a *wish list the host honors*. Skills that previously ..."
  },
  "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": "7f6bd6697c126a41252c40ca3da7585b85c2dc7e3cb3da0e7f7ce1684e5c6e34",
    "verified_classes": [
      "UnverifiableCapabilityError"
    ],
    "verified_functions": [
      "_selector_is_canonical",
      "validate_manifest",
      "load_skill"
    ],
    "verified_functions_count": 3,
    "defensive_guards_count": 2,
    "raised_exceptions": [
      "UnverifiableCapabilityError"
    ],
    "sample_fail_closed_invariants": [],
    "stdlib_dependencies": [],
    "observation_mode": "EMPIRICAL_BOUNDARY_CAPTURE",
    "zero_external_deps": true
  }
}