cache_status

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

The annotations already declare readOnlyHint=true and openWorldHint=false, and 'Makes no network call' usefully corroborates the closed-world, side-effect-free profile in plain language. It also adds the important scoping fact that results cover only this session, not a global history. However, with no output schema, the description leaves the report's actual shape and size undocumented.

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?

Two short sentences with no filler, and the substantive claim (what is reported) is front-loaded before the clarifying constraint about network calls. Nothing here could be cut without losing 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?

For a zero-parameter, read-only diagnostic with no output schema, the definition covers the essentials: what is reported, its session scope, and that it is a local operation. The only gap is that a caller cannot predict the return structure, which the absence of an output schema pushes back onto the description.

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 tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline applies. No parameter-level guidance is needed or missing.

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 names a specific verb and resource: reporting this session's requests broken down by site plus cache use. That is clearly distinct from the search-style siblings, but the description never explicitly contrasts itself with them, and the phrasing 'by site, and cache use' is slightly loose about whether cache use is reported per-site or in aggregate.

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?

'Makes no network call' implies this is a cheap local diagnostic an agent can call freely, e.g. before deciding whether a search is needed, but the description never states when to use it, when not to, or what alternative to pick. Usage must be inferred from the network-free property rather than stated.

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