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

readOnlyHint=true already tells the agent this is a safe read, so the bar is lower. The description adds useful return context (all field values, membership level and status) and explains the extended_membership_info switch, but says nothing about error behavior for a missing/invalid contact_id or any rate limits.

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 with the core verb and payload front-loaded. The trailing raw endpoint restatement ('Wild Apricot: GET /accounts/...') is marginally useful routing info but is essentially redundant given the tool already targets that API.

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 two-parameter read with no output schema, the description does describe the shape of the returned data, which is the main gap-filler. It still omits not-found/error behavior and pagination/expansion caveats, leaving the agent under-informed on edge cases.

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 both parameters are already documented in the schema, making 3 the baseline. The description only restates the extended_membership_info purpose (pending order, invoice, allowed actions), adding little beyond the schema text.

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 ('Fetch one contact or member') and names the returned payload (all field values, membership level, status), which implicitly contrasts with the sibling list_contacts. It stops short of naming an alternative tool explicitly, so it falls just short of a 5.

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 description never says when to reach for this tool versus wildapricot_list_contacts, update_contact, or check_in_attendee. Usage is only inferable from 'one contact'; no prerequisites, no exclusions, no alternatives are stated.

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