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

With no annotations, the description carries the full burden. It does disclose two genuinely useful behaviors beyond the schema: the API silently forces IsActive and Status to true, and authentication is handled automatically via the `x-api-key` header. It omits what happens on duplicate email, whether the call is idempotent, and what the response contains (e.g., the new member id), which matters for a mutation tool.

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 the core action, then the forced-field caveat, then the auth note. No filler or restatement of the name/title.

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 four-required-parameter create tool with no output schema and no annotations, the definition covers inputs and auth but leaves the outcome underspecified — the agent cannot tell what is returned or how failures (duplicate email, invalid country code) manifest. Adequate but with clear gaps for a mutation.

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%, with all four required parameters documented including format hints and examples. The description adds nothing beyond the schema about parameter meaning — it only alludes to "contact details" and clarifies that IsActive/Status are not parameters at all.

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?

"Creates a member using contact details" gives a specific verb (creates) and resource (member), and the schema confirms the contact-detail inputs. It is clearly distinct from read-side siblings like get_member, though it does not explicitly contrast itself with the other create_* tools.

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?

Usage is implied rather than stated: the agent learns an API key is required and that IsActive/Status cannot be supplied, but there is no guidance on when to create a member versus looking one up first (get_member), nor any mention of duplicate-email handling or prerequisites such as an existing booking.

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