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

Annotations cover the safety profile (readOnly=false, destructive=false). Beyond that, the description adds genuine value: it discloses that new proxies start with `proven` false because FeelingSurfViewer validates before sessions, plus the 403 `proxy_limit_reached` cap behavior and 422 `validation_error` on duplicates. This is richer behavioral context than the annotations alone provide.

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?

Front-loaded with the core purpose, then two dense sentences carrying validation and error semantics with no padding. Slightly compressed phrasing ('FeelingSurfViewer checks it before any session goes through it') but every clause earns its place.

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 5-param create tool with no output schema, the definition supplies the mutation semantics, the initial `proven` state, and the two salient failure modes. Missing only an explicit statement of the response payload or required permissions, which are minor given the coverage.

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 description coverage is 100%, so the schema already documents every parameter including host/port validation rules, the type enum, and username/password socks5 constraints. The description adds no parameter-level detail beyond the schema, so the baseline 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?

States a specific verb+resource ('Add a proxy') and clarifies it 'registers a static proxy', distinguishing it from update_proxy and list_proxies. It does not name any sibling explicitly, but the registration semantics are clear enough to separate it from the related proxy tools.

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 implies insertion of a new proxy but gives no explicit when-to-use vs update_proxy or when-not-to-use condition. The error notes (duplicate host/port returns 422) implicitly tell the agent to use update when the proxy already exists, but this routing is left to inference.

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