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

readOnlyHint=true already establishes this is a safe read, lowering the disclosure burden. The description adds the useful context that output is de-nested/flattened versus raw FHIR. However, it says nothing about permissions, pagination, or response size, so it adds only modest value beyond the annotation.

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 tight sentences with the format distinction front-loaded, followed by the filtering note. The endpoint string is mildly redundant but conventional and not wasteful.

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?

With no output schema, the description usefully frames the return format as flattened/de-nested data, and the annotation covers the safety profile for a 3-parameter read tool. Minor gaps around pagination and update semantics remain but are not blocking for correct invocation.

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 coverage is 100%, so all three parameters are documented in the schema. The description only restates the optional domain filter and adds nothing about the _since timestamp or the patient id format. Baseline 3 is appropriate when the schema carries the parameter detail.

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 (Retrieve) and resource (patient clinical data) and characterizes the output as Particle's flattened/de-nested format. The phrase 'easier to read than raw FHIR' implicitly distinguishes it from the particle_get_fhir sibling, but it doesn't name that alternative directly, so differentiation relies on inference.

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?

'Optionally filter to one domain' hints at a use case, but there is no explicit guidance on when to choose this over particle_get_fhir, particle_get_fhir_by_type, or particle_get_ccda. Usage is implied rather than stated.

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