Export a whole library

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the agent knows it's a safe read. The description adds valuable behavioral context: it pages to exhaustion, returns a compact list, and reports how many pages were fetched and whether the cap truncated the result. This discloses the pagination and truncation behavior beyond what annotations contain.

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 three sentences long and each sentence adds value: the first states the action and result, the second provides usage guidance with examples, and the third reports on output metadata. It is front-loaded with the primary purpose and contains no filler, making it highly efficient.

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 description covers the essential context: what the tool does, when to use it, the pagination and truncation behavior, and hints at filtering. It also implicitly addresses cost by mentioning how narrowing can reduce requests. Since there is no output schema, the description's mention of a 'compact list' and reporting of pages fetched provides a reasonable picture. Minor gaps: it doesn't list all filter parameters explicitly or detail response structure, but the schema and enums fill some of that in.

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 only 29% (username and max_games have descriptions). The tool description mentions 'a genre filter' as an example but does not explain each filtering parameter. It frames some parameters as 'filters' but leaves their formats ambiguous (e.g., release_year is a string without format details). The description does not compensate sufficiently for the low schema coverage.

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: to page a library query to exhaustion and return a compact list of every match. It distinguishes itself from single-page queries by explicitly saying 'rather than a single page', and provides concrete example queries ('which of my backlog are space sims') that make the resource and scope unmistakable.

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 explicitly states when to use the tool: 'Use when you need to reason over the entire set... rather than a single page.' It also gives practical advice on narrowing with filters first, even including an example of how a genre filter can reduce the number of requests. This clearly positions it relative to alternatives like query_library despite not naming them directly.

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