Add a photo to an offer

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

Goes well beyond the annotations: it discloses the state gate (offer in review), that Vereel downloads https URLs versus uploading a file from the server's machine, the 5 MB and 6-photo caps, that the first photo becomes the cover, and the auth requirement. These are exactly the operational facts an agent needs before calling a non-idempotent, open-world write.

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 tight sentences, front-loaded with the action and its precondition, followed by the input choice and then the limits. No filler or restatement of the title.

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?

Covers preconditions, input modes, format/size/count limits, cover ordering, and auth. The only gap is the return value and what happens when the offer isn't in review; with no output schema, a brief note on the response would have made it complete.

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 already 100%, so the baseline is 3, but the description adds real value by framing imageUrl and filePath as mutually exclusive alternatives and clarifying where filePath resolves (the server's machine, not the caller's). It doesn't state behavior if both are supplied, but the added semantics exceed the schema text.

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 ("Add one photo to an offer") plus a scoping condition ("still in review"), which cleanly separates it from siblings like vereel_create_offer and vereel_update_offer. An agent knows exactly what this does without opening the schema.

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 clear preconditions (offer must be in review, read-and-write brand token required) and the either/or choice between imageUrl and filePath. It does not explicitly name sibling alternatives or say what to do if the offer is no longer in review, but the context for use is unambiguous.

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