Upload Blob

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

Annotations already indicate this is a non-read-only, non-destructive mutation. The description adds valuable behavioral context: it returns a blob key and does not attach the blob to a document. This clarifies the tool's side effects without contradicting 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?

The description is only two sentences long and front-loaded with the core action and outcome. Every word earns its place, with no redundancy 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?

Given the tool's simplicity and the extensive schema coverage, the description provides sufficient context: what the tool does, what it returns, and its key limitation (not attaching to a document). It could mention constraints like size limits, but these are likely outside the tool's core behavior, and the output schema is present to clarify return values.

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 fully describes all five parameters with precise meanings and defaults. The description does not add any parameter semantics beyond the schema, so the baseline of 3 is appropriate.

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 the tool's function: 'Upload a file or blob into AFFiNE workspace storage and return its blob key.' It uses specific verbs and resources, and explicitly distinguishes it from siblings by noting it 'does not attach it to a document by itself.'

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 implies when to use the tool (for storing content in workspace storage) and gives a boundary condition ('does not attach it to a document by itself'), suggesting other tools are needed for attachment. It doesn't name explicit alternatives, but the context is clear enough for an agent to select appropriately.

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