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

Beyond annotations (readOnlyHint=false, destructiveHint=false), the description adds significant behavioral details: no account/email required, daily rate limits, payment behavior (x402 response), and ethical constraints (never pays targets, respects robots.txt). This fully informs the agent about side effects and restrictions.

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 a single well-structured paragraph that front-loads key points. Every sentence adds value without redundancy or unnecessary detail.

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?

Given the tool's simplicity (1 param, output schema exists), the description is comprehensive: covers purpose, limitations, payment behavior, and ethical stance. It is sufficient for an AI agent to select and invoke correctly without ambiguity.

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 schema describes 'url' as a public website URL, and the description adds that it must be HTTP(S) and that the audit is robots-compliant and bounded. This adds meaning beyond the schema, though the schema coverage is 100%.

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 explicitly states it starts a free bounded, robots-compliant audit of one public HTTP(S) page. It distinguishes from siblings like start_paid_audit and get_audit_status by specifying the free nature and limitations.

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 provides clear context on when to use the tool: for free audits, no account needed, one per IP/website per day. It mentions the daily limit and payment behavior but does not explicitly state alternatives or when not to use, leaving some inference to the agent.

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