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

With annotations already declaring the mutation and destructive profile, the description adds valuable context beyond them: the agent's AI context is rebuilt in the background 'usually within a minute,' and the response's `message_weight` and optional `notice` are explained. It does not cover permission errors, though the agent_id schema does.

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 purpose and avoids filler. The sentence about `message_weight` is slightly dense but earns its place by explaining the response without an output schema.

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 create tool with no output schema, the description usefully explains the background rebuild and response fields. However, it leaves the required `name` parameter and `tags` array undocumented anywhere, which is a notable gap for an agent trying to invoke this 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?

Schema coverage is only 50%, and the description adds no meaning for the undocumented required `name` parameter or the `tags` array. The content and agent_id parameters are already well-documented in the schema, so the description does not compensate for the coverage gap.

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 and resource: 'Add knowledge to an agent' and 'Text knowledge, linked to the agent.' An agent can tell this creates a text knowledge entry for an agent, but it does not differentiate from siblings like replace_knowledge_base or create_attachment.

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 phrase 'Text knowledge, linked to the agent' implies this is the tool for adding new text knowledge, but there is no explicit when-to-use guidance and no mention of when to prefer replace_knowledge_base or other alternatives.

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