Diagnose cache graph

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

Annotations already set readOnlyHint=true, and the description reinforces this with 'never mutates' and 'Plans only'. It adds valuable context about the outputs (findings, patch ops, narration) and the flow. No contradictions with annotations; the description enhances behavioral understanding beyond the hint.

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 concise—two sentences—and front-loaded with the core action. Every clause adds value: the first sentence states what it does and what it returns, the second clarifies safety and the relationship to patch_cache. No redundancy or filler.

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?

The tool is moderately complex with a nested parameter and an output schema. The description covers the main outputs and the non-mutating nature, and it mentions the sibling patch_cache to complete the workflow. While it doesn't dive into cache format details or edge cases, the presence of an output schema and the clear workflow make it sufficiently complete for selection and basic usage.

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 0% for parameter descriptions, so the description must compensate. However, it only says 'serialized cache' without detailing the required structure, expected format, or any constraints beyond the schema's generic object shape. This is insufficient for an agent to correctly construct the 'cache' parameter, especially given its nested complexity.

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 the tool runs a full inspect -> reason -> plan graph over a serialized cache, and distinctly distinguishes from siblings by mentioning the output is patch operations to feed into patch_cache. It specifies the resource (cache) and the action (diagnose), making it unambiguous and differentiated.

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 indicates when to use this tool: to get findings and proposed patch operations without mutating anything. It says 'Plans only; never mutates' and points to patch_cache for the actual application, giving clear workflow context. It doesn't explicitly say when not to use it (e.g., for targeted inspection with inspect_dangling_refs), but the intent is clear.

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