rules_get_entry

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

With no annotations, the description carries the full burden. It discloses that the entry includes 'description, traits, raw data' and that matching is by 'exact name' or slug. However, it does not state behavior for missing entries, multiple identifiers provided, or error conditions. The 'Provide exactly one' hint partially covers misuse but not edge cases.

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 a single sentence, front-loaded with the action and resource. Every clause adds value: what is fetched, via which identifiers, and the exclusivity constraint. No filler or repetition.

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?

The tool has an output schema, so return values don't need description. The description covers the essential input constraint and the nature of the output. Minor gaps include not-found behavior and error handling, but the overall context is sufficient for a low-complexity fetch tool.

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 has 0% description coverage, so the description must compensate. It explains that id, name, and slug are alternative selectors and that exactly one must be provided. This adds meaning beyond the raw schema (which only lists nullable properties with defaults), though it does not detail the format for each identifier.

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 clearly states the tool's function: 'Fetch a single PF2e entry's full detail (description, traits, raw data) by id, exact name, or slug.' It uses a specific verb ('Fetch') and resource ('single PF2e entry'), and distinguishes from siblings like rules_search by emphasizing 'single' and 'full detail'.

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 provides clear usage context: it fetches a single entry by exactly one of three identifiers, with the explicit constraint 'Provide exactly one of the three.' However, it does not explicitly mention when to prefer this over alternatives like rules_search or rules_related, so it misses the 'when-not' guidance for a 5.

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