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

Annotations only state readOnlyHint=false and destructiveHint=false, so the description carries the burden of disclosing behavior. It does so by revealing the rewrite side effect, atomic batch application, and chain resolution. However, it doesn't mention error handling, rollback, or permissions, which are less critical but still relevant for a mutating tool.

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 dense but every sentence adds value: main function, format example, preference rationale, constraint, and batching semantics are all present without fluff. It is front-loaded with the core purpose, though a bit long for a simple rename tool.

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 rename tool without an output schema, the description covers the essential aspects: what it does, how to specify renames, constraints, and batch behavior. It lacks return-value details and error-case notes, but these are often predictable. Given the tool's complexity, this is sufficiently complete.

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%, so the description must compensate. It clarifies the 'renames' parameter with an example and the no-extension rule, which adds meaning. But it says nothing about 'projectId' or 'expected_version', leaving those under-specified for a tool with 0% schema coverage. The partial clarification earns a middle score.

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 a specific action ('Rename one or more items') with a key side effect ('automatically rewrite every file that imports them'). It distinguishes from delete+create and implies a precise use case, making it easy to differentiate from sibling tools like copy_file or delete_file.

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?

Provides explicit guidance: 'Preferred over delete+create', clarifies the required name format ('Use item names WITHOUT extensions'), imposes a constraint ('Same type only'), and explains batching behavior ('atomic in ONE pass' with chain resolution). This tells the agent exactly when and how to use the tool versus alternatives.

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