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

Annotations already establish that this is read-only, idempotent, and non-destructive, so the description does not need to repeat those facts. The description adds the exact-path constraint and sibling routing, but does not disclose additional runtime behavior such as encoding, error handling, or output details. With annotations covering the safety profile, this is adequate but not rich.

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 crisp sentences with no filler. The primary usage rule is front-loaded, and the exclusion/alternative guidance follows immediately. Every sentence earns its place.

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 straightforward multi-file read tool with full schema coverage, an output schema present, and safety annotations already provided, the description is complete enough for correct invocation. It tells the agent when to call it, what parameters are required, and how it differs from related tools.

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 100%, and the schema already documents that paths are absolute, max 50 per call, and that device is required. The description slightly reinforces the 'exact path' semantics, but this is mostly a usage guideline rather than new parameter meaning. Baseline 3 is appropriate.

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 ('read') and resource ('multiple file paths'), with the exact condition 'two or more exact file paths'. The description explicitly distinguishes itself from read_files and read_file, so an agent can select it correctly without inspecting sibling schemas.

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?

Gives direct when-to-use guidance: use for two or more exact file paths. Also names alternatives for glob discovery (read_files) and single known paths (read_file), making the routing decision explicit.

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