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

readOnlyHint=true already declares the safety profile, so the description only needs to add context. It does add value by disclosing the exact FHIR path and that the result is a FHIR searchset Bundle, but it says nothing about pagination behavior, error cases, or authentication needs.

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 short, front-loaded sentences with no filler: purpose first, then the concrete FHIR mapping, then the return shape. Every sentence carries information the agent can act on.

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 low-complexity, single-required-param read tool, the description covers purpose, API mapping, and return type even though no output schema exists. It does not explain how multi-page searchset Bundles should be traversed, which is the only real gap.

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% and both parameters are documented in the schema, so the baseline is 3. The description only restates patient={id} via the URL template and adds no format, validation, or paging semantics beyond the schema.

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 ('List a patient's allergies/intolerances') and even pins the exact FHIR interaction (GET /AllergyIntolerance?patient={id}), making it clearly distinguishable from list_conditions, list_medications, and other list_* siblings. It stops short of explicitly routing the agent away from any sibling, but the resource name is unambiguous.

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?

Usage is only implied by the name and endpoint; there is no stated when-to-use, when-not-to-use, or comparison to alternatives such as get_patient_everything or fhir_search. An agent can infer the intended case (fetching allergy data for a known patient id) but the description adds nothing explicit.

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