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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds real behavioral context beyond that: synchronous execution ($async=false) and the backing REST endpoint. It does not describe the response shape, but the read-only nature and sync behavior are the key facts.

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, front-loaded with the mode-selection distinction. The API endpoint citation is marginally redundant for tool selection but harmless and confirms the resource.

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?

Given 8 optional params, no output schema, and full schema coverage, the description supplies what the schema cannot: the choice logic between the two query styles and query syntax examples. Remaining params (count, ids_only, select, sort) are adequately documented in the schema itself.

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 baseline is 3. The description goes further by explaining the semantics of the two most complex params (simple_query vs filter), including OData operator examples and pointing to wildapricot_list_contact_fields for field names.

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 (search contacts and members) and even cites the underlying endpoint GET /accounts/{accountId}/contacts. It is distinguishable from get_contact and list_contact_fields, though it never names a sibling to explicitly contrast with.

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?

Clearly routes between the two query modes: simple_query for substring matching vs filter for OData expressions, with concrete examples. It does not state when to prefer a different tool entirely (e.g. get_contact for a known id), so it stops short of explicit exclusions.

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