vision_from_file

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It doesn't mention that this invokes a Gemini model call (with associated cost/latency), doesn't explain what the returned output looks like, doesn't disclose any failure modes (e.g., unsupported file formats, large-file limits), and doesn't mention the compact parameter's effect of history compaction. The behavior of using an external AI model is a non-trivial side effect that should be disclosed.

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 a single concise sentence: 'Describe a single file (image, audio, video, or text) using Gemini.' It front-loads the core purpose with no wasted words and no redundant repetition of the schema fields. Highly efficient.

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 omits key context: that Gemini is an external AI service with potential cost/latency implications, that different file types (audio/video) have different processing requirements, and any guidance on how to craft the prompt parameter. It does have an output schema, which lessens the need to explain return values, but for an AI-invoking tool with multiple media types, more completeness is expected.

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%, so all four parameters (path, type, prompt, compact) are documented in the schema. The description adds the media-category context (image, audio, video, or text) which maps to the type enum, but doesn't add detail about any parameter beyond what the schema already provides. At 100% coverage the baseline of 3 applies, and the description adds minimal additional semantics.

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 'Describe a single file (image, audio, video, or text) using Gemini' uses a clear verb (describe) with a specific resource (single file) and media categories. The 'single' qualifier distinguishes it from plural sibling tools like vision_from_files, from_files, and vision_from_resources. However, it doesn't explicitly differentiate from vision_from_resource, which also does single-resource description.

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?

There is no guidance on when to use this tool vs. siblings. The description doesn't mention when to prefer vision_from_file over vision_from_resource, from_file, vision_from_files, or vision_from_files_mixed. No exclusions or alternative recommendations are given, which is a significant gap given the large sibling set with overlapping purposes.

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