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

The annotations already state that this is not read-only, is idempotent, and is not destructive. The description adds important behavioral context by stating that the operation replaces all attachments and that every document must belong to the workspace. It does not explain permissions or response behavior, but it adds meaningful replacement semantics beyond the annotations.

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?

Two short sentences, front-loaded with the core action and followed by the key constraint. There is no wasted wording.

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 two-parameter mutation with full schema coverage and meaningful annotations, the description provides the essential replacement semantics and the workspace constraint. It does not describe return values or permission requirements, but it is largely complete for correct invocation.

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 parameter definitions already carry most of the burden. The description adds a semantic validation rule not present in the schema: all supplied knowledge documents must belong to the workspace. That gives useful extra meaning for the nested knowledge_ids list.

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 clearly states a specific verb and resource: replace all attached knowledge documents. It also adds the workspace ownership constraint. It does not explicitly distinguish this from sibling tools such as set_assistant_tools, but the resource is specific enough to identify the 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 phrase 'Replace all' implies the use case is complete replacement rather than incremental attachment, but the description does not explicitly say when to use this versus related tools or when not to use it. Usage is therefore implied rather than fully guided.

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