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

With no annotations, the description carries the full burden, and it does disclose two useful traits: the operation is additive rather than replacing, and it requires bearer-key auth. It omits failure behavior, duplication/dedupe semantics, and whether appends are reversible.

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?

Two short sentences, zero filler, with the action front-loaded and the auth prerequisite trailing. Nothing extraneous.

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?

With no annotations, no output schema, and 0% parameter documentation, the description is too thin for a write tool: the events payload format, record targeting via site_id, and result behavior are all left unspecified.

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 0% and the description explains neither parameter. Critically, 'events' is an array of untyped objects whose expected shape is undocumented in both schema and description, and site_id's format/meaning is unstated.

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?

The description names a specific verb+resource ('Append service events') and constrains it to 'an existing record', which separates it from creation-style siblings like create_site. It does not, however, explicitly contrast itself with sibling tools such as check_service_record or get_record_summary.

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?

'Append ... to an existing record' implies the usage context (adding to a record that already exists) and states a prerequisite ('Requires a bearer key'). There is no explicit when-not guidance and no named alternative for related operations.

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