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

With no annotations, the description carries the burden of behavioral disclosure. It states that the entire published docs site is bundled, skill pages are included, multiple URL/slug forms are accepted, and omitting the slug lists every page. This is more transparent than typical fetch descriptions, though it does not cover errors or return details.

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?

Three sentences, each carrying useful information, with the core action front-loaded. No filler or redundant phrasing. The format flexibility and list behavior are packed into a compact, readable structure.

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 single-optional-parameter fetch tool with no output schema and no annotations, the description covers the main decisions: what to pass, what formats are accepted, and what happens if nothing is passed. It does not state the return payload shape, but for a doc-fetch tool 'can be read in-band' implies the content is returned. The only real gap is explicit routing to search_docs for unknown slugs.

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 schema only describes the slug as a doc slug with one example. The description adds significant meaning: accepted input forms (bare slug, leading slash, #anchor, full URL, older redirects) and the default behavior when the slug is omitted. This substantially enriches the parameter semantics beyond the schema.

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 action and resource: "Fetch any page of the Alter documentation by slug." It distinguishes itself from sibling search_docs by emphasizing retrieval via a known slug/URL, and it even covers the list-every-page fallback. The resource scope is unambiguous.

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 clearly implies this tool is for fetching known documentation pages, especially when you have a slug, URL, or redirect. However, it does not explicitly mention when not to use it or name alternatives like search_docs for discovery. The guidance is useful but mostly implicit.

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