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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds useful confirmation via the GET endpoint and clarifies the range of entity types returned, but it does not mention not-found behavior, permissions, or response characteristics; with annotations present, this is an adequate but modest contribution.

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 two compact sentences with no wasted words. The core action and scope are front-loaded, and the endpoint path is a useful secondary detail rather than filler.

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 single-parameter read-only lookup with full schema coverage and an explicit readOnlyHint annotation, the definition is nearly complete. Minor omission: it says nothing about what happens when the id does not resolve, but for this simple tool that gap is small.

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 the schema already explains that the id comes from the matching list tool and provides a pattern constraint. The description adds only the general notion of fetching by id, so baseline 3 is appropriate when the schema carries the detailed parameter semantics.

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 uses a specific verb ("Fetch") and resource ("organization"), and it enumerates the concrete entity subtypes covered: practice group, clinic, funder, external practice. Combined with "by id" and the endpoint path, an agent can readily distinguish this from the sibling list tool halaxy_list_organizations.

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 id" implies this is for direct lookup when an identifier is already known, and the schema notes the id comes from the matching list tool. However, the description itself does not explicitly state when to use this instead of halaxy_list_organizations or what to do if the id is unknown.

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