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

Annotations already indicate destructiveHint, and the description reinforces this with 'MUTATES' while adding non-obvious behavior: the API uses PUT with only-included-fields-change semantics, and the id is never sent in the request body. This goes beyond the bare annotation and helps the agent understand the operation's side effects.

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?

Three sentences, each with a distinct purpose: identify the operation, state the HTTP semantics, and clarify the two non-obvious parameter behaviors. No filler, no repetition of schema definitions.

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?

Combined with the exhaustive schema and destructiveHint annotation, the description covers operation type, endpoint, partial-update behavior, and the path/body split. It does not describe return values, but no output schema exists and the required parameter is already documented in the schema.

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%, so the baseline is 3, but the description adds meaningful parameter guidance: the `fields` passthrough is the correct way to send current_version/body, and it merges over typed fields. The note that id is path-only prevents a common invocation error.

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 states a specific verb ('updates') and resource ('existing article'), and the leading 'MUTATES' clearly signals a write operation, distinguishing it from read/list/create siblings. The explicit endpoint further pins down the exact operation.

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 makes clear this tool is for modifying an existing article, and the partial-update semantics ('only included fields change') convey when it is appropriate relative to create/get alternatives. It does not name sibling tools explicitly or state when not to use it, but the context is sufficiently obvious.

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