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

Annotations only supply destructiveHint=true and a title, so the description usefully reinforces that this mutates live data ('REAL ... live practice', 'POST /individual_appointments') and notes the ends_at fallback. It does not disclose conflict/double-booking behavior, idempotency, or return payload, so it stops short of full transparency.

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?

Front-loads the critical WRITE/REAL warning, then lists requirements compactly in three sentences with little waste. The required-parameter enumeration is mildly redundant given the schema but does not bloat the text.

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 destructive write with no output schema, the definition covers inputs and the mutation warning but omits what the call returns (e.g. the created appointment id) and how failures such as slot conflicts are surfaced. Adequate but with clear gaps.

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%, and each parameter's meaning and required status is already documented in the schema. The description restates the five required fields (redundant) and repeats the ends_at default rule, adding no syntax or format detail beyond the schema — the baseline 3.

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 — 'books a REAL new individual appointment' — and contrasts it with the read-oriented siblings (cliniko_get_appointment, cliniko_list_appointments) by naming it a WRITE. An agent can tell this is the creation tool without opening the schema.

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 'WRITE — books a REAL new ... live practice' framing implies when to use it (a real booking versus a lookup), but it never states prerequisites or alternatives, e.g. that cliniko_list_available_times or cliniko_next_available_time should be consulted first to find a valid slot. Usage is implied rather than explicit.

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