gemini_import_file_to_store

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

Annotations already mark this as a non-read-only, non-destructive, non-open-world write. The description adds the meaningful behavioral fact that the call returns an operation object for tracking progress, i.e. it is asynchronous, which is not derivable from annotations and matters for an agent's follow-up handling. It does not disclose auth needs or any mutate-vs-reference semantics.

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?

Three short sentences with zero padding: what it does, when to reach for it, and what it returns, in that order. Nothing restates the name or title and nothing could be dropped without losing information.

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?

With no output schema, the description usefully compensates by stating the return is an operation. The only real gap is not pointing at the sibling operation-polling tool for the async follow-up, which would close the loop for a multi-step import flow.

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 description coverage is 100% and all three parameters, including the custom_metadata shape and its 20-item cap, are documented in the schema. The description adds no parameter-level detail, so the baseline 3 applies.

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?

States a specific verb and resource chain: import a file from the Gemini Files API into a File Search store. The scenario sentence ('large files that were uploaded separately via the Files API') implicitly separates it from the sibling gemini_upload_to_store, but no sibling is named, so an agent must still infer the boundary.

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?

Gives a clear selection condition: use this when the file was already uploaded separately via the Files API, which contrasts with an upload-from-scratch path. It stops short of naming gemini_upload_to_store as the alternative or stating a when-not condition, so it is clear context without explicit routing.

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