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

Annotations only declare the generic profile (readOnlyHint=false, idempotentHint=false, destructiveHint=false); the description goes well beyond by disclosing that the link is single-use, expires in 30 minutes, accepts PDF/JPG/PNG up to 4 MB, and can be consumed either via browser or as multipart/form-data (field 'file') or a raw body. That is exactly the operational context an agent needs and cannot get from the structured fields.

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?

Four dense sentences that are front-loaded with the return value and scope, then usage, then mechanics, then follow-up. Every sentence carries information, though the HTTP-POST sentence and the browser-upload sentence could be tightened slightly without loss.

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?

With no output schema and only two params, the description still covers what comes back (uploadUrl), its lifetime and one-time nature, accepted formats and size, both submission methods, and the correct next tool to call. Nothing needed to invoke it correctly is missing.

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%, so both leiId and document are already fully documented in the schema, including the source tools for leiId. The description restates the document categories but adds no format, constraint, or edge-case detail beyond the schema, so baseline 3 applies.

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?

States a specific verb and resource (returns a one-time upload link / uploadUrl) and scopes it to concrete document types: limited POA, transfer POA, or supporting documents of a new LEI application. An agent can immediately distinguish it from the sibling base64 upload tools (upload_registration_document, upload_signed_limited_poa, upload_signed_transfer_poa).

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?

Explicitly names the alternative and the condition that selects it: 'Use this instead of the base64 upload tools for any file you can't pass exactly as text, which is most PDFs.' It also prescribes the follow-up path (check_registration_status or check_transfer_status) and both invocation modes (user browser vs. direct HTTP POST).

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