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

Annotations only indicate that the tool is not read-only and not destructive. The description adds that it mutates an existing note by appending markdown to the end, which clarifies ordering and non-replacement behavior. It does not cover error behavior, auth, or idempotency, but those are less critical for a simple append operation.

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?

One sentence captures the action, target, format, and position, with no filler or redundancy. Every element earns its place.

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 simple append with three parameters and an output schema, the description plus annotations cover the essential operational facts. Alternative-tool guidance is absent, but nothing necessary for actually invoking the tool 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 documentation covers only if_updated_at, so the description must carry meaning for id and content_markdown. It does: id identifies the existing note to append to, and content_markdown is the markdown to append. It omits length or format constraints, but the core parameter semantics are clear for a 3-parameter tool.

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 names a precise operation—'Append markdown to the end of an existing note's body'—and the end-of-body semantics naturally separate it from update_note and replace_in_note. It clearly identifies the resource and the action.

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 verb and target imply the intended use: adding content to the end of an existing note rather than replacing or editing in place. However, the description never explicitly says when to prefer this over replace_in_note or update_note, so the guidance remains inferred.

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