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

Annotations cover the safety profile (not read-only, idempotent, non-destructive), and the description adds traits the annotations cannot: `fields` replaces the entire list rather than merging, that list must contain an 'email' field of type 'email', and booking success mode requires an event_type_id whose hours/duration live on that event. It also states the return ('Returns the updated form').

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?

Four sentences, front-loaded with identity and scope, then the two hard constraints. No filler and every sentence carries an actionable rule.

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 28-parameter mutation with no output schema, the description covers the return value and the critical gotchas (full field replacement, required email field, booking dependency). It leaves many optional flags dependent on schema text alone, but nothing dangerous is 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?

With 28 parameters at 61% schema coverage, the description compensates by explaining the highest-risk semantics: how `form` accepts id or slug, that `fields` is a full replacement with a mandatory email entry, and the `success_mode: booking` / `event_type_id` linkage. It does not cover the remaining ~39% of undocumented parameters, so it stops short of a 5.

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 ('Update a Smart Form's configuration') and adds a frame of reference ('the same fields the form editor saves') that tells the agent exactly which surface it touches. This clearly separates it from create_a_form, delete_a_form, duplicate_a_form, and publish_a_form.

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?

Gives partial-update instruction ('Pass `form` (id or slug) plus only the fields to change') and a conditional dependency ('success_mode: "booking" needs an event_type_id from list_events'). It does not explicitly say when to prefer publish_a_form or get_form over this tool, so sibling routing is implied rather than stated.

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