check_for_updates

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

The description discloses useful behavior beyond the annotations, namely that it compares against PyPI and returns upgrade instructions rather than performing an upgrade. However, it explicitly says the tool checks PyPI, an external network service, while the annotations declare openWorldHint=false (closed-domain interaction); the readOnlyHint=true and idempotentHint=true hints are consistent, but this external-lookup claim conflicts with the open-world declaration and should be reconciled.

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?

A single, front-loaded sentence with no filler: verb, source (PyPI), target package, and the returned artifact all appear in order. Nothing is repeated from the title or schema, and no sentence is wasted.

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 zero-parameter, non-destructive utility with no output schema, the description covers what the tool does and what the caller gets back (version comparison plus upgrade instructions). A minor gap is that it does not say what happens when the environment is offline or the lookup fails, but the core call path is fully specified.

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 tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. The description correctly implies a no-argument call to check the installed package against the index.

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 gives a concrete verb and resource ('Check PyPI for newer versions of free-image-library') plus the follow-on outcome ('get upgrade instructions'). It is clearly distinct from the sibling tools (find_audio, find_images, image_roulette, skill_read, skills_list), though that separation is inferred from the subject matter rather than stated explicitly.

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?

Usage is only implied by the wording ('check ... newer versions' suggests calling it to detect available updates) and by the phrase 'upgrade instructions,' which hints it is a precursor to an upgrade step. There is no explicit statement of when to call it, when not to, or which tool to use instead if the user just wants to install or pin a version.

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