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

Annotations already indicate readOnlyHint=false, destructiveHint=false, and idempotentHint=false, so the tool is a non-read, non-destructive write operation. The description adds valuable behavioral context beyond that: it states the DOCX file is immutable and only metadata can be updated, which is a key constraint not captured in annotations. It also notes for the delete action (included in the description) that deletion is irreversible, though that's not directly relevant to this update tool. No contradiction with 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 organized in a bulleted action list, making it scan well. It includes create and delete actions even though this tool is only for update, adding some extra content that could be trimmed, but the flattened action marker helps isolate the relevant part. Each sentence adds value: the metadata limitation, field lists, and immutability notice are all useful. Slightly verbose but not wasteful.

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 write/update tool with no output schema, the description is fairly complete. It explains what can be updated, notes the immutability constraint, and indicates the required token parameter. It doesn't describe return values or error scenarios, but such details are often not necessary in MCP descriptions when an output schema is absent. Overall, it provides enough context for an agent to correctly invoke the update operation.

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?

The input schema has 0% description coverage and only lists generic properties (data, account, template_token) without detail. The description compensates by enumerating the updatable fields inside the data object (name, lang, observers[], first_signer, folder_path/token, redirect_link) and clarifies that template_token is required for the update action. It also distinguishes required fields for create but not for update, providing clear semantic meaning beyond the bare schema.

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 the tool manages ZapSign templates and explicitly describes the 'update' action: 'update (template_token, data): metadados (o DOCX em si é imutável)' with a list of updatable fields. The flattened action marker '[Flattened action: update]' confirms this tool is specifically for updating templates, distinguishing it from sibling create/delete tools.

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 provides implicit usage context: it notes the DOCX itself is immutable, so only metadata can be updated. It lists the fields that can be changed, which helps an agent know when to use this tool (to modify template metadata). However, it does not explicitly state 'use this instead of create/delete' or mention any prerequisites, so it's clear but not fully explicit about when not to use it.

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