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

readOnlyHint=true already establishes the safe read profile, so the description's main remaining job is minor. It adds only an implementation note ('Engine API: GET /search') rather than useful behavioral context such as result shape, ordering, or rate limits. No contradiction with annotations.

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?

Two compact sentences with the core purpose front-loaded and no wasted words. The trailing 'Engine API: GET /search' is mildly implementation-detail padding but harmless.

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 7-parameter search tool with a nested age object and no output schema, the description covers the purpose but says nothing about what results look like or how filters interact, which the absent output schema would otherwise need. Adequate but with clear gaps.

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 every parameter (phrase, age, sex, types, dev_mode, model_id, max_results) is already fully documented in the schema. The description adds no parameter meaning beyond that, which is the correct baseline when the schema does the heavy lifting.

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 ('Search') plus resource ('medical concept database') and scope ('observations matching a phrase'), with '(autocomplete)' clarifying the interaction style. This is clear and distinguishable from the get_/list_ siblings, though it never names them explicitly.

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 parenthetical '(autocomplete)' implies the intended use (type-ahead lookup of concepts by phrase), but there is no explicit when-to-use/when-not guidance and no alternatives named against siblings like list_symptoms or get_symptom. Usage must be inferred.

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