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

The description discloses behavior well beyond the annotations: Proofestry does not store the page, records are timestamped via RFC 3161 with a permanent proof link, failed fetches with 4xx/5xx are never charged, and the price is 0.02 USDC per URL. These are consequential cost, retention, and failure details an agent cannot derive from `readOnlyHint=false` or `openWorldHint=true`.

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 dense but front-loaded with the core action and its outputs before moving to constraints and pricing. The only wasted element is the trailing 'MCP tool: `snapshot_citation`.' which merely restates the tool name.

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?

For a two-parameter tool with full schema coverage and no output schema, the description covers the return record, retention policy, cost, failure handling, and fetch limitations. An agent has everything needed to decide and to call it correctly.

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?

With 100% schema coverage, the baseline is 3, but the description adds real meaning by explaining why to set `include_content`: the service never stores content, so this flag is the only way to keep the bytes. That rationale goes beyond the schema's own description of the flag.

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 opens with a specific verb and resource: 'Fetches a public web page and records what it served,' then lists the exact recorded fields. This is far more precise than the title alone. It doesn't contrast itself with siblings such as `timestamp` or `snapshot_citations`, so the agent must infer the distinction from context.

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?

Usage is mostly implied by the constraints: only public http(s) pages on ports 80/443, and pages requiring login or JavaScript are captured as served to a plain request. There is no explicit 'use this instead of X' routing or statement of when a different tool is the better choice, leaving the agent to infer the boundary from sibling names.

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