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

Goes well beyond the annotations by disclosing operational behavior: reads once with robots.txt respected, never issues tools/call, re-reads daily, and returns capture id, time and SHA-256 hashes. It also states cost/auth posture (free, no account) and the receipt-only side effect, which explains why readOnlyHint=false while destructiveHint=false.

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?

Four tight sentences, front-loaded with purpose, then behavior, then constraints. Every sentence carries information; the only mild redundancy is restating the public/non-personal constraint already implied by 'public MCP server'.

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?

No output schema exists, but the description supplies the essential return shape (capture id, time, SHA-256 hashes), the read semantics, the side effect, and the input constraints. Nothing an agent needs to call this correctly is missing.

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%, so the schema already documents both url and protocol (including the enum and the /.well-known inference rule). The description reinforces that url is the required input but adds no format or constraint detail beyond what the schema provides, so the baseline of 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?

Names a specific verb (save) and resource (dated record of what a public MCP server or A2A agent card declares now), and explicitly rules out what it is not ('Not an assessment'), which separates it from assessment-oriented siblings like check_agent_conformance. An agent can identify the target class (MCP endpoint or A2A card) without opening the schema.

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?

Gives clear context: use this to snapshot a public server/agent card, pass its url, inputs must be public and non-personal. The 'Not an assessment' line implicitly excludes the conformance-checking alternative, but no sibling is named explicitly, so the routing is implied rather than spelled out.

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