Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds real value beyond that: offline re-verification with no callback, no live probe/no network/instant, and explicit caution that it is 'verification status only - NOT a safety, quality, or trust verdict'. It stops short of specifying response shape in full, but the extra context is substantial.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The purpose is front-loaded, but the middle is bloated with parenthetical marketing about SaSame/GEC and the observation ledger that does not help an agent call the tool. The key operational facts (miss vs hit counters, offline verification, audit_mcp fallback) are buried rather than ordered for scanning.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries the burden of explaining returns, and it does: the measured fields (reachable/callable/schema-valid/grade/last-measured) and the feed_size-on-miss / observation_count-on-hit counters. It also states the offline-verification contract, making it largely sufficient for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and there is a single parameter, so the schema already documents the url field and its accepted forms. The description adds only 'any MCP/agent endpoint' and no extra syntax or format guidance, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The opening sentence names a specific verb (look up) and resource (an existing, ed25519-signed Readiness attestation) for MCP/agent endpoints, and later distinguishes itself from audit_mcp for the not-yet-observed case. The core purpose is unambiguous, though it is surrounded by tangential corporate/GEC framing that dilutes the signal.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives some routing guidance: use the returned record if observed, 'call audit_mcp' if not yet observed, and contrasts itself as a pure read with 'no live probe'. However it does not clarify when to prefer this over near-neighbors like readiness_report, verify_mcp_ready, or lookup_registry_entry, leaving much to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.