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

The annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds useful domain context — that results include entities from installed extensions and carry a short description, and that it maps to APIv4 Entity.get — but says nothing about result shape, ordering, or size.

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 sentences, front-loaded with what is returned, followed by how to use the output and the underlying API call. No filler and no redundancy with the schema.

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 simple, no-required-param discovery tool with annotations and no output schema, the description covers discovery, scope (core + extensions), and downstream usage. Only minor gaps remain, such as whether results are paginated or sorted.

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?

There is a single optional parameter with 100% schema description coverage ("Only entities whose name or title contains this text"), so the schema already carries the semantics. The description never mentions filtering, which is acceptable at this coverage level but adds no value.

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+resource: lists the APIv4 entities available on this site, with concrete examples (Contact, Contribution, Event) and the extension caveat. It also scopes itself relative to siblings by naming civicrm_get_fields and civicrm_query as the consumers of its output.

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?

"Use the names with civicrm_get_fields and civicrm_query" positions this clearly as the discovery step before those tools, which is real routing guidance. It stops short of explicit exclusions (e.g., skip this if you already know the entity name), so it is not a 5.

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