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

Annotations already declare readOnlyHint=true, so 'non-mutating' adds little. However, the description goes beyond annotations by disclosing the return shape (array of matching patient objects) and the empty-result behavior (204 message when none match) — meaningful since no output schema exists.

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 compact sentences, front-loaded with purpose before return behavior and endpoint. Every sentence carries information, though the raw endpoint URL is arguably meta-detail rather than agent-facing guidance.

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 13-parameter, 8-required search tool with no output schema, the description covers purpose, return shape, and no-match behavior. It could note lifecycle or matching-threshold behavior, but for correct invocation it is essentially complete.

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 all 13 parameters are already documented in the schema with types, enums, and formats. The description adds only the general notion of demographic matching, not syntax or field-level semantics beyond what the schema provides — baseline 3.

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 states a specific verb and resource ('Search for an existing patient by demographics'), which clearly distinguishes a demographic-search operation from an ID-based lookup like particle_get_patient. It stops short of naming that sibling explicitly, so the differentiation is inferable rather than stated.

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 phrase 'by demographics' implies the usage context (use when you don't have a known patient ID), but there is no explicit when-to-use, when-not-to-use, or named alternative against particle_get_patient. Guidance is implied rather than prescribed.

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