pg_summary

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

No annotations are provided, so the description carries full burden. It states '[READ]' indicating no side effects and describes the output (histogram + list). However, it does not disclose any permissions needs, performance implications for large clusters, or the exact format of the list. Basic transparency is present but lacks depth.

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 compact: a one-line title, a sentence explaining usage, and an Args section. It is front-loaded with purpose. While very concise, it could be slightly better organized by separating the Args into a proper list or using bold for emphasis, but it remains efficient and clear.

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 low complexity (1 optional parameter, no output schema), the description explains purpose and parameter adequately. However, it omits details about what 'every PG that is not active+clean' means exactly, potential error conditions, or how the histogram is returned. For a health summary tool, a bit more context about interpretation would improve completeness.

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 sole parameter 'target' has no schema description (0% coverage). The description adds meaning: 'Ceph target name from config; omit for the default.' This tells the agent where the value comes from and that it is optional, effectively compensating for the schema gap.

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 opens with '[READ] PG state histogram + every PG that is not active+clean.' This clearly specifies a read operation and the exact resource being summarized: histogram of PG states and listing of non-healthy PGs. The rhetorical question 'are my PGs healthy?' reinforces the tool's purpose, and it is distinct from siblings like pg_dump_stuck or pool_ls.

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 explicitly says 'Call this to answer "are my PGs healthy?"' which is a clear usage context. It does not provide explicit when-not-to-use or alternatives, but the context and sibling list imply this is the primary summary tool for PG health, making the guidance effective.

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