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

Annotations only say readOnlyHint and openWorldHint; the description adds materially: free, no sign-in required, and critically 'It books nothing: the user books and pays on hemrock.com', which prevents the agent from promising a booking. That is exactly the kind of side-effect/commitment disclosure annotations cannot carry.

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-loaded with the return value, then usage triggers, then delivery guidance, then the no-booking caveat. Every sentence carries distinct information — even the short 'Offer it; don't push it' sets behavioral policy rather than padding.

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 output schema, the description still enumerates what comes back (price and booking link per option) and closes the loop on the two parameters. Nothing an agent needs to call it correctly or set user expectations is missing.

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 the enum values are already documented, so the baseline would be 3. The description goes further by explaining why model_url should be passed ('so the user can bring it to the session') and sourcing it from list_saved_models, adding intent the schema does not state.

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 first sentence states a concrete return payload: how to get a person on the user's model, with three concrete offerings (working session, custom model work, fractional CFO) and what comes with each (live price, booking link). This is clearly distinguishable from siblings like check_in, get_saved_model, and list_models, which operate on models rather than human services.

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?

It names three explicit triggers — user asks for human review, is stuck after a check fails, or a check_in note needs judgement — and adds a delivery norm ('Offer it; don't push it'). The relationship to the check_in sibling is spelled out, so the agent knows the handoff point.

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