Digest several files

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

Beyond the annotations (readOnly, openWorld, idempotent), the description discloses additional behavior: per-file output ('Each file keeps its own last line') and partial failure handling ('a file that cannot be read says so in its place rather than taking the others down'). This enriches the annotation-only context.

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 somewhat wordy and repetitive, e.g., 'asked at the same time' and 'asked together' convey the same idea. It could be more concise while retaining the essential points.

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?

While the description covers high-level batching and error handling, it omits important context such as parameter meanings, output format details beyond a per-file line, and how 'budget' or 'keep' affect behavior. This leaves agents under-informed given the tool's complexity.

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 description provides no explanation of the parameters ('paths', 'keep', 'budget'). Schema coverage is 0%, and the description does not compensate; it only vaguely references file lists without naming or defining any parameter.

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's purpose: 'Digest several files in one call' with the verb 'digest' and resource 'files'. It differentiates from single-file alternatives by emphasizing batching, e.g., 'come back as one tool result instead of four'.

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?

Explicit usage condition: 'Use it whenever there is more than one file to read'. It also contrasts with multiple individual calls ('four logs cost four waits... roughly one wait') and describes error behavior for unreadable files, providing clear guidance.

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