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

Annotations already indicate read-only, non-destructive, non-idempotent, open-world behavior, but the description adds critical operational details: cost per call, free failed calls, first 25 calls free, and that repeats are not free because each call is charged. It also reinforces that the tool only reads/computes and changes nothing.

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 front-loaded with purpose and usage, then adds pricing and safety context efficiently. It is slightly dense but every sentence is relevant to an agent deciding whether and how to call the 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?

With no output schema, the description supplies the return shape (a few sentences plus bullet key points), usage boundaries, input limit, and cost/auth behavior. An agent has enough context to call it correctly and understand the main operational constraints.

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%, so the schema already documents both parameters thoroughly. The description restates the 12,000-character input limit but does not add meaning beyond the schema for the sentences 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 states a specific verb and resource: summarize up to 12,000 characters of supplied text into a few sentences plus bullet key points. It also distinguishes the URL case by directing agents to /summarize, making the tool's scope clear.

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?

It names concrete use cases (long emails, documents, transcripts, tool outputs) and explicitly routes web-page-by-URL work to the /summarize alternative. This is clear when-to-use guidance rather than implied context.

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