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

Annotations already declare readOnlyHint: true, and the description reinforces this with 'Read-only; makes no legal ownership decision.' The description adds significant behavioral context beyond annotations by detailing the verification steps (claimant signature, artifact digest, event chain, timestamp binding, false qualified-timestamp states) and the offline capability. The trailing paragraph about SaSame is irrelevant but not contradictory. Overall, it adds useful behavioral detail, so a 4 is appropriate.

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 first two sentences are concise and front-loaded with the core purpose. However, the third sentence about SaSame observing the MCP ecosystem and MCP Factory is entirely unrelated to the tool's function, adding noise and length. This violates conciseness; every sentence should earn its place, and this one does not. The fluff drags the score down to 2.

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?

The tool has one parameter and no output schema, so the description must explain what the tool returns or the nature of the result. It lists checks but does not specify the output format (e.g., pass/fail, detailed report, error conditions). Additionally, the irrelevant marketing paragraph detracts from completeness. An agent calling this tool would be uncertain about the response structure, making a score of 2 appropriate.

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 coverage is 100% – the only parameter's description ('Complete SaSame Provenance & Rights Passport JSON object') fully documents it. The tool description restates this and adds that verification checks specific components, but it does not elaborate on the passport structure or parameter format beyond the schema. Given high schema coverage, baseline is 3; the description adds marginal semantic value without requiring a higher score.

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 description clearly identifies the tool as 'offline-compatible verification of a SaSame Provenance & Rights Passport JSON object' and enumerates the specific checks performed (Ed25519 signature, artifact-set digest, event hash chain, etc.). It also explicitly states it is read-only and makes no ownership decision. This is a specific verb+resource that differentiates it from likely siblings like lookup_passport (which may return registry data) or provenance_passport_spec (which likely returns the spec).

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?

The description implies usage: verify a passport you already have, and mentions 'offline-compatible' suggesting it can be used without network. However, it provides no guidance on when to use this versus alternatives (e.g., when to use lookup_passport or onchain_read_verified) and no exclusions. The usage context is clear but not fully explicit, so it earns a 3 rather than lower.

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