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

Annotations only cover the safety profile (write, non-destructive, closed-world). The description goes well beyond them: it discloses the return shape, states bytes never pass through the tool, documents the one-hour uploadUrl expiry, and describes downstream verification via request_create.

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?

Single tight paragraph, front-loaded with the purpose, then the return contract, then the required follow-up steps. No sentence is filler; even the load_skill pointer adds routing value.

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?

There is no output schema, but the description inlines the returned fields ({ id, uploadUrl, expiresAt, name, contentType, size }) and the complete two-step upload handoff, so an agent has everything needed to invoke and chain the tool 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?

Schema coverage is 100% with per-field descriptions and constraints (max size, enum content types, sha256 pattern), so the schema already carries the parameter meaning. The description reinforces the workflow linkage (declared Content-Type, id reused as documentId) but adds no unique per-parameter detail, matching the baseline-3 rule.

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?

Starts with a specific verb+resource ('Reserve an upload for one document... through the form's Documents block'), clearly identifying the object and the mechanism (upload reservation, not the file transfer itself). It distinguishes itself from the request-side siblings by naming the follow-on tool request_create and the Documents block context.

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 an explicit end-to-end workflow: call this to reserve, PUT bytes to uploadUrl within one hour, then pass { documentId: id } into request_create's documents. It also notes 'one upload serves any number of requests' and points to load_skill("requests"), so the agent knows the surrounding process as well as the trigger condition.

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