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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds two things beyond that: the response format is markdown and only published guides are served, which is the key behavioral constraint an agent needs. It stops short of saying what error or empty result an unknown slug produces.

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 compact clause with the lookup key and the returned sections front-loaded; no filler, no repetition of the title.

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 one-parameter read tool with no output schema, the description covers the returned sections and the format, which is what an agent most needs. The remaining gap is failure behavior for missing or unpublished slugs, a minor omission given full annotation coverage.

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 coverage is 100% and the slug property already carries a description with an example and a pointer to search_build_guides. The description only restates that the lookup is by slug, adding no format, casing or validation detail beyond the schema, so this sits at the baseline.

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?

States the resource (a published build guide) and the lookup key (slug) plus the returned content shape: parts, assembly steps, connections and firmware. That distinguishes it from search_build_guides, which returns multiple candidates, though the description never explicitly frames it as a retrieval-by-identifier operation.

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 phrase 'by slug' implies the caller already has an identifier and therefore has already used search_build_guides, and the word 'published' hints at a constraint. There is no explicit when-to-use statement, no named alternative, and no stated behavior when the slug is invalid or the guide is unpublished.

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