read_image

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

Beyond the readOnly/idempotent/non-destructive annotations, the description discloses the 4 MiB size cap and that image bytes are returned to the requesting AI. This adds meaningful runtime behavior. It stops short of describing error cases, but annotations already cover the safety profile.

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, each carrying information: the action and formats, the size limit, and the return behavior. Nothing is redundant and the core purpose is front-loaded.

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 one-parameter read-only tool with strong annotations and no output schema, this description covers purpose, allowed inputs, size limitations, and return behavior. An agent has enough to invoke it 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?

With 0% schema coverage, the description helps by listing accepted image formats and the size limit, but it never explicitly states that 'file' is a path/identifier to a local image file. The parameter name plus format list makes the meaning inferable, but the description does not fully compensate for the missing schema documentation.

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 names the exact verb ('View'), the resource (image files), and the supported formats (PNG, JPEG, GIF, WebP), and clarifies that the operation is direct rather than via public upload. This clearly differentiates it from siblings like read_file and file_info.

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?

It gives clear context: use this tool when an AI needs to see image bytes directly without public exposure. It does not explicitly list when-not conditions or name alternatives, but the scope is specific enough to route an agent correctly.

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