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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds real behavioral context beyond them: the accepted formats and 4 MB cap, that content must be base64 text, and what happens downstream ('Global FinReg then checks the transfer and sends it to the LEI's current issuer'). It stops short of describing the response or failure modes.

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?

Front-loaded with the core action and constraint, then the routing alternative, then the downstream effect. It is dense with parentheticals but every clause carries information; nothing is filler.

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?

No output schema exists, so the description correctly explains what happens after upload. Combined with annotations covering idempotency and non-destructiveness, an agent has enough to call it correctly; only the return/error shape is left implicit.

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 the baseline is 3 and the schema already explains both parameters. The description nonetheless adds meaning for 'content' that the schema omits – accepted formats (PDF/JPG/PNG) and the 4 MB size ceiling – and frames 'leiId' as a transfer awaiting its POA.

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 ('Uploads the transfer POA the user has signed by hand'), plus the file formats and size limit, and distinguishes itself from the sibling get_upload_link and from upload_signed_limited_poa. An agent can tell exactly which upload path this is.

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 boundary condition ('Only for files small enough to pass exactly as text') and the alternative with its exact argument ('for anything else (most PDFs) use get_upload_link with document "transfer_poa"'). It also adds a precondition guardrail: only upload a POA the user gave you as signed.

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