Attach a knowledge base to an agent

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

Annotations already mark this as a non-read-only, idempotent, non-destructive operation, and the description adds useful behavioral detail: the result reports attachments before and after, and for multi-prompt agents the API accepts the attachment but cannot verify it. This goes beyond what annotations alone convey and helps the agent interpret the response.

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 front-loaded with the core purpose, followed by important behavioral semantics and the prerequisite lookup step. Each sentence adds necessary information, and nothing is redundant or filler.

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?

The description covers the purpose, the additive behavior, the response shape, an important API edge case, and how to find a required parameter. With no output schema present, this level of detail is sufficient for an agent to invoke the tool correctly.

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 agent_id and kb_id, and the schema description coverage is 100%. The description reinforces that kb_id comes from list_knowledge_bases, but it does not meaningfully add new semantic detail beyond the 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 uses a specific verb and resource combination: 'Attach a knowledge base to an agent' and states the intended effect ('so it can answer from those documents during calls'). It also clarifies the additive nature ('does not replace existing attachments'), which differentiates it from the sibling detach_knowledge_base without needing to name it.

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 clear context: the tool is for adding an attachment, is additive, and does not replace existing attachments. It also tells the agent to use list_knowledge_bases to find a kb_id. It does not explicitly say 'use detach_knowledge_base instead when removing an attachment,' but the additive guidance makes the intended selection clear enough.

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