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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=false; the description adds real context beyond that by explaining the two-part result (presigned URL + document metadata) and that the file is persisted on the enquiry. The explicit 'does not submit a credit decision' caveat prevents an agent from conflating this with a decisioning call. Auth requirements, URL expiry and any overwrite behavior are still unstated.

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 short sentences with the action stated first, followed by the persistence detail and then the exclusion. No filler, and each sentence carries distinct information.

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 write tool with five undocumented parameters, no output schema, and no description of the returned presigned URL (expiry, HTTP method, how to POST the file), the description leaves too much for the agent to infer. The core exclusion is covered, but the operational mechanics an agent needs to complete the upload flow are absent.

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 0% and none of the five parameters (id, fileName, enquiryId, documentType, applicationId) is explained in the description. The phrase 'existing SecureLend enquiry' weakly implies enquiryId matters, but the schema marks zero required parameters, so the description cannot be said to clarify requiredness or the id-vs-applicationId distinction. This is a clear miss against a low-coverage schema.

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 names a specific verb+resource pair: it creates a presigned upload URL plus document metadata tied to an existing SecureLend enquiry. It also carves out what it is not ('does not submit a credit decision'), which separates it from the offer-processing siblings. It does not, however, distinguish itself from display_upload_documents_form, the closest sibling.

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?

There is no explicit when-to-use guidance and no named alternative. The only directional signal is the negative clause about not submitting a credit decision, which is an exclusion rather than a routing instruction. An agent must guess whether to call this or display_upload_documents_form.

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