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

Annotations only indicate that the tool is not read-only, not open-world, and not destructive. The description adds meaningful behavioral context: new keywords start as PENDING, are auto-promoted to ACTIVE when they fit the plan, and excess keywords remain PENDING until activation. It does not cover edge cases like duplicate handling, but the core state-transition behavior is well disclosed.

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 compact and front-loaded with the primary action, followed by essential behavioral details in a clear sequence. Every sentence earns its place, and there is no redundant restatement of the tool name or schema fields.

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?

Given the small parameter surface, 100% schema coverage, and presence of an output schema, the description is complete enough for an agent to call the tool correctly. It explains the critical plan-dependent behavior and directs the agent to the relevant sibling tool for excess keywords, leaving no major gap.

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 already documents both required parameters (websiteId and keywords) with descriptions, giving 100% schema coverage. The description does not add parameter-level detail, but it does not need to because the schema fully covers semantics. This meets the baseline for schema-driven parameter clarity.

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 uses a specific verb and resource — 'Add keywords to a website' — and then clarifies the lifecycle (PENDING → ACTIVE) so the tool is clearly distinguished from siblings like delete_keyword, edit_keyword, and activate_pending_keywords. It states the core action and its immediate behavioral consequence.

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 clearly names the follow-up/sibling tool activate_pending_keywords for keywords that remain PENDING, and explains the plan constraint that determines when that tool is needed. This gives an agent an explicit decision rule: adding keywords is the right move for creating keywords; activation is handled separately.

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