add_document

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

With no annotations, the description carries the full burden and does disclose the critical input constraint: the file must be a base64 data URL with an explicit example. It does not say what happens on duplicate uploads, size or MIME limits, required permissions, or whether the document then becomes visible to compliance review.

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?

Two sentences, zero filler, with the operation and target front-loaded and the format constraint second. Nothing could be removed without losing 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 five-parameter mutation with full schema coverage and no output schema, the description supplies purpose, target objects and payload format. It stops short of covering behavioral outcomes (post-upload visibility, error conditions) that an agent would want before invoking a write tool.

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 schema already documents all five parameters including the enums and their defaults. The description only reinforces the base64Url format with an example, adding minor value over the schema. 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 ('Attach a supporting document') plus the two attachment targets (transfer or payment route deposit). This is clearly distinguishable from siblings like list_documents, get_document_download_url and delete_document, which operate on already-existing documents.

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?

Offers one concrete use case ('for example when Stables compliance asks for one'), which implies when to reach for it. However, it never mentions alternatives such as submit_rfi_evidence when an RFI is open, nor any when-not-to-use condition, so routing among document-related siblings is left to inference.

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