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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the returned field set (RecordID, name, email, phone, entity link, active flag), which is useful since there is no output schema, but it says nothing about pagination behavior or result caps beyond what the schema's top/skip already state.

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 tight sentences: capability first, filter semantics second, the RecordID caveat third. No repetition of schema constraints and no filler; even the endpoint reference is a single trailing clause.

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 five-parameter, zero-required read tool with no output schema, the description covers what is listed, how to scope it, and the return fields, while pagination and field selection are fully documented in the schema. An agent has everything needed to call it correctly on the first attempt.

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 the baseline is 3, and the description goes further by clarifying that entity_id is the Customer/Vendor RecordID and warning not to confuse it with a Contact's RecordID — a semantic distinction the schema does not spell out. It adds no extra detail on select or text beyond the schema wording.

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 and resource ('List contacts (people)') plus the two filtering modes (entity_id scoping, text matching) and names the backing endpoint. It is immediately distinguishable from siblings such as method_search_customers or method_list_activities, which operate on different resources.

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?

Explains the two ways to narrow the list and gives a concrete downstream rule of thumb ('Use a Contact's RecordID (not the Customer's) when linking activities'). It does not, however, say when to prefer this over method_query_records or method_search_customers, so tool selection across siblings is left to inference.

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