download-bytes

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

With readOnlyHint=true already provided, the description adds valuable behavioral context by disclosing the exact return shape ({ contentType, encoding, contentLength, contentBytes }) and warning about the base64-through-context approach for large files. This goes beyond the annotation's 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?

The description is concise and well-structured: it opens with the core action, lists supported use cases, states the return format, and then provides alternative guidance. Every sentence earns its place, and the most critical information 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?

The description covers the return format, usage alternatives, and the parameter is fully documented in the schema. There are no missing details that an agent would need to call the tool correctly, making it complete for a single-parameter read operation.

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%, with the 'target' parameter fully documented via examples. The tool description itself does not add parameter-level semantics beyond what the schema already provides, so the baseline score 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 states a specific verb ('Download'), resource ('Microsoft Graph'), and return format ('base64'), and enumerates supported content types (drive files, mail attachments, profile photos, Teams content, meeting recordings). It differentiates from get-download-url by explicitly naming the alternative for large files, making the intent unmistakable.

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 gives explicit when-to-use guidance: it recommends get-download-url for large drive/SharePoint files and get-meeting-recording-content for meeting recordings. It also frames the tool as the 'single tool' for general binary reads, giving clear context for when it is the right choice.

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