start_scan

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

Adds context beyond annotations: enqueues async job, returns immediately with scanId, fetches/renders the site (not read-only), and describes caching. Annotations provide readOnlyHint=false, which is consistent.

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 sentences, each with a distinct purpose: purpose, behavior, return/caching, next step. No redundant information.

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?

Despite no output schema, the description explains the return shape, caching, and the asynchronous nature. All necessary context is covered.

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% and schema description is thorough. The description does not add significant new meaning beyond what the schema already provides for the url parameter.

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 states it starts a release-readiness scan for a public URL across five layers, distinguishing it from sibling tools like get_scan and compare_scan_history.

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?

Explicitly says 'Use this first, once per site' and 'do not busy-loop calling start_scan for the same URL', and provides the next step to poll get_scan. Also explains caching behavior.

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