list_libraries_tool

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

With no annotations, the description carries the full burden and does well: it discloses the return shape (dictionary mapping library names to version lists), the case-insensitive filter behavior, and the fallback action of prompting the user if a library is missing. It could mention side effects or limits, but this appears to be a safe read/list operation.

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 well-structured and front-loaded with purpose, then return format, usage, and fallback. The Args section is concise and clear, though it would be stronger if it matched the schema.

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 simple listing tool, the description covers purpose, behavior, and fallback well. However, the mismatch between the documented search_term argument and the empty input schema creates a real ambiguity that prevents the agent from confidently invoking the tool.

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 documents an optional search_term parameter with meaningful semantics, but the input schema declares zero properties. This is a direct contradiction: an agent cannot tell whether passing search_term is valid. The 0-param baseline is 4, but the misleading documentation lowers the score substantially.

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 identifies the tool's purpose: retrieving available documentation libraries/frameworks and their versions. It uses a specific verb and resource, and it distinguishes itself from sibling tools by framing this as a pre-search discovery step.

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 explicitly says to use this tool before performing a search, which gives clear usage context. It does not name sibling alternatives or state when not to use it, but the 'before a search' positioning is enough to guide selection.

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