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

Annotations only declare readOnlyHint=false and destructiveHint=false, so the description usefully adds that this is a partial update (only supplied fields change), that the full object is returned, and how Space scoping applies. It lacks detail on failure behavior for an unknown keyword_id and leaves the 'created' wording unexplained, keeping it below a 5.

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 short sentences, front-loaded with the action and partial-update semantics, followed by return value and scoping. No redundant restatement of the name or title; every sentence carries information an agent needs.

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 mutation tool with nested _native payloads and no output schema, the description covers partial-update semantics, the return shape, and Space scoping, which is the material an agent needs. Remaining gaps are edge cases (nonexistent keyword_id, whether 'created' implies upsert), so it is complete but not exhaustive.

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 67%: space_id is richly documented in-schema and body carries a KeywordUpdate description plus _native replace semantics, so the schema does most of the work. The description only adds example body fields (matchType, status) and says nothing about keyword_id or the partial-merge rule, so it does not compensate for the gap — baseline 3.

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+resource ("Partial update of a keyword") and gives example fields (matchType, status), which separates it from create_keyword/delete_keyword by verb alone. It doesn't explicitly name a sibling to choose between, and the phrase "updated/created object" slightly muddies whether this can create, so it falls short of a clean 5.

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 explains Space scoping (use set_active_space to switch, or pass space_id to override for this call), which is real usage context. However it never says when to use update_keyword versus create_keyword or get_keyword, and gives no prerequisites such as needing an existing keyword_id, so guidance is implied rather than explicit.

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