lookup_concept

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly states exact-match behavior, the return type (Concept or None), and the absence of a match returning None. While it doesn't discuss edge cases like malformed codes, the core behavior is transparent for a lookup 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: purpose, usage guidance, parameter definition, and return behavior are each given in clear, non-redundant sentences. No unnecessary words 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?

Given the single parameter, the sibling context, and the presence of an output schema, the description is complete. It tells the agent when to use it, which sibling to use instead, what input to provide, and what to expect in return. Nothing essential is missing.

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 0%, but the description compensates by defining concept_code as 'an exact ICD-10-CM code' with a concrete example ('E11.21'). This adds meaningful semantics beyond the bare string type in the schema, though it doesn't specify formatting or normalization rules.

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 a specific verb and resource: 'Look up a single ICD-10-CM concept by its exact billing code.' It also explicitly differentiates from search tools, making it clear this is an exact-code lookup rather than a free-text query.

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 explicitly says 'Use this when the caller already has a specific code' and contrasts with 'search_concepts' for free-text clinical terms. This provides clear when-to-use and when-not-to-use guidance, directly routing the agent to the correct sibling tool.

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