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

The description fully discloses that the tool 'Reads the stored register: it contacts nothing and measures nothing.' It also honestly explains that 'absent and pending are reported honestly and are NOT negative verdicts' and clarifies that 'verified' can never be false, ensuring the agent understands the reliability and side-effect-free nature of the operation.

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 description is concise but includes essential details about the return fields, trust implications, and the read-only nature. It is structured as a coherent paragraph with clear sentences, though slightly verbose due to repeated emphasis on what the tool does not do.

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 description outlines the return values (verified, state enum, measured_at, record_sha256, recompute_url) and explains how to verify the verdict without trusting the gate. It also mentions the alternative for fresh measurements. It lacks explicit error handling details but is sufficiently complete for an agent to decide on usage.

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?

The only parameter 'endpoint' is already well-described in the input schema as an 'https URL... exactly as it appears on the register.' The description does not add extra semantics beyond the schema, but since the schema covers 100% of the parameter, the baseline of 3 is appropriate.

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 precisely states the tool's purpose: 'A single machine-first answer for an agent deciding whether to trust an MCP endpoint BEFORE it connects.' It also explicitly differentiates from the sibling tool check_conformance, making its unique role clear.

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 indicates when to use the tool ('BEFORE it connects') and provides an explicit alternative for fresh measurements ('use check_conformance'). This gives clear contextual guidance on when to employ this tool versus a sibling.

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