Read a guidance document

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

The description goes well beyond the readOnly/idempotent annotations by disclosing the 25,000-character truncation behavior, the 'section' retrieval semantics, and detailed error handling for unknown ids and unmatched headings. An agent can predict important edge-case behavior before calling the tool.

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 compact and well-structured: a one-sentence purpose, a behavior paragraph, an Args list, and an Error handling line. Every sentence adds information and there is no repetition of schema content.

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 two-parameter read-only tool, the description is complete: it explains source of ids, optional section behavior, truncation, and error responses. Even without an output schema, an agent has enough information to select and invoke the tool correctly.

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 already documents both parameters clearly, but the description adds useful nuance: 'section' is a substring, it retrieves the heading plus subheadings, and omitting it returns the whole truncated document. The examples 'specificity' and 'permutation' help clarify acceptable inputs.

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 first sentence states the exact operation: 'Fetch one guidance document, or one heading within it.' This clearly conveys the verb, resource, and optional narrower scope, and it is easily distinguished from sibling tools like lnm_list_guidance.

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 gives concrete guidance on when to use the 'section' parameter: pass part of a heading to get one section, or omit it for the full document. It also points to lnm_list_guidance as the source for valid ids, though it does not explicitly name alternatives or state when not to use this tool.

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