get_usage_summary

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful interpretive context beyond that: the figures do not represent remaining account quota, which prevents a plausible misuse of the returned data. It still says nothing about granularity, currency, or freshness.

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?

A single compact sentence with zero filler, front-loading the resource and scope and reserving the trailing clause for the important non-quota caveat.

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?

With no output schema, the description carries the burden of explaining return values, yet it only says 'token 与费用统计' without units, currency, or breakdown, and both parameters are undocumented in the schema. Adequate to call the tool, but an agent cannot predict the response shape.

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 0% and neither parameter is described in the schema. The description only implicitly gestures at the two modes ('单次' vs '最近多次'), leaving the agent to guess that run_id selects one run and limit bounds a recent-run list; it does not document the limit's default, range, or the meaning of run_id's format.

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 (读取) and resource (Codex/Claude token 与费用统计) with a scope covering single or recent multiple runs. It is distinguishable from siblings like list_runs and get_run_status, though it never names those alternatives explicitly.

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 phrase '单次或最近多次任务' implies the two usage modes (a specific run vs. recent history), which maps loosely to the run_id/limit split, and the closing caveat clarifies what this is not. However, there is no explicit when-to-use guidance or named alternative tool for related questions.

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