Update Letter

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

Annotations already indicate readOnly=false and destructive=false, so the description doesn't need to restate that. It adds valuable behavioral context: the partial-update semantics ('Send only the fields to change') and the effect of setting published=false to hide the letter. This goes beyond the annotations.

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?

The description is two sentences, action-first, and every word contributes value. It names the resource, the targeting strategy, the update semantics, and the published field's behavior without any filler.

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 straightforward update tool with strong schema coverage and annotations, the description sufficiently covers how to target a letter and the key update behavior. It doesn't mention return values or error handling, but given the lack of an output schema and the simple nature of the operation, this is adequate.

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 86% and field descriptions are detailed. The description adds a key semantic not in the schema: the tool performs a partial update, so only provided fields are changed. This clarifies the update model beyond what the schema alone communicates.

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 clearly states 'Update a Playbook letter by id or slug' with a specific verb and resource, distinguishing it from create/delete/list/get letter siblings. It is precise and immediately identifies the tool's function.

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 description implies usage for modifying an existing letter, but it doesn't explicitly contrast with create_letter or delete_letter. The partial-update guidance ('Send only the fields to change') gives some direction, but alternatives are not named, so the when-to-use is only implied.

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