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

Adds a critical behavioral disclosure beyond the readOnly/destructive annotations: 'ksao_type/canon_component_id are null by design where unresolved — treat null as not yet joined, never as no link.' This corrects a likely misreading of null results and materially changes how an agent interprets output. No contradiction with openWorldHint=false — this is null semantics within the returned set, not a claim about exhaustiveness of results.

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 earning its place: purpose, then usage recipes, then the null-semantics caveat. The defining scope is front-loaded and the description contains no filler, repetition of schema text, or restatement 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 12-parameter tool this is nearly complete: the schema documents every parameter, an output schema exists, and annotations carry the safety profile. The description supplies the usage recipes and the null caveat that schema fields alone couldn't convey. The only gap is the absence of explicit routing guidance against the three sibling tools.

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 100%, so the baseline is 3. The description adds value above baseline by wiring parameters into usage patterns — min_guides=2 for the cross-cutting spine, role for job requirements, capability_detail for the hydration mode switch — which the individual parameter descriptions do not convey.

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 a specific verb and resource — 'Traverse the capability spine joining books, guides (capability packages), KSAO-grade elements and jobs' — which clearly delimits the cross-entity nature of the query surface. This differentiates it from the sibling tools (get_guide, list_guides, list_taxonomy), which operate on single entity types.

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?

Gives explicit parameter recipes: 'Use min_guides=2 for the cross-cutting capabilities', 'role=<role> for what a job requires', 'capability_detail=<slug> for one package with its elements and books hydrated'. These are strong when-to-use-signals, but the description never names sibling tools or states when NOT to use this tool in favor of get_guide/list_guides/list_taxonomy.

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