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

The readOnlyHint annotation already covers the safety profile, so the bar for behavioral disclosure is lower. The description adds a concrete behavioral trait beyond the annotation: PDFs and images are returned as the actual document so tables and scans preserve fidelity, which is useful for an agent deciding if this tool is appropriate. It does not discuss size limits or OCR behavior, but those are not necessary for the read-only context.

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 sentences with no filler: purpose, when-to-use, behavioral note, and parameter routing are each delivered in one tight sentence. The most important information is front-loaded, and the examples ('schedules, itineraries...') earn their place by clarifying the document types.

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 simple read-only tool with only two optional params and no output schema, the description is complete: it tells the agent how to locate the file, which identifier to pass, and what to expect back for PDFs/images. There is no output schema, so the explicit note about return format for non-text files is appropriately included.

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 the baseline is 3. The description rises above by clarifying the relationship between the two parameters: object_id is the preferred route from search_graph_objects, while name is a fallback used when the object_id is unknown. This adds workflow semantics the schema alone doesn't convey.

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?

Description opens with a specific verb and resource ('Read the content of a file the user uploaded') and immediately restricts its scope to documents in the user's Second Brain with concrete examples (schedules, itineraries, contracts, exports, scans). This makes it distinguishable from sibling read tools and search tools without requiring schema inspection.

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 states exactly when to reach for this tool ('use this when the answer may live in a document in their Second Brain') and gives the lookup workflow: search_graph_objects with type 'file', then pass object_id or a filename fragment as name. It does not explicitly name alternative read tools and say when not to use them, so it stops one step short of full exclusion guidance.

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