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

With no annotations, the description carries the full disclosure burden and does so thoroughly. It explains the keyless signing flow, that calls without an envelope return action_required='sign_envelopes', how to sign and re-call, the 307-redirect to GCS, that bytes never transit the MCP server, and that one file per call is allowed in envelope mode.

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?

The description is longer than a trivial tool description, but the added length is justified by the non-obvious direct-upload and signing flows. It is front-loaded with the core result and every sentence adds a distinct decision or behavioral fact rather than repeating schema 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?

The description fully accounts for the important runtime context: upload URL generation, finalization via nukez_confirm, byte passthrough, large-vs-small file routing, and keyless authentication. Since an output schema exists and no annotations are present, this is a complete description for correctly selecting and invoking the 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?

The description gives strong semantics for envelope, including the exact signed spec and the re-call requirement, which goes meaningfully beyond the schema. However, it does not explicitly explain content_type or receipt_id, and the schema itself provides no descriptions, so the description only partially compensates for the low schema coverage.

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 first sentence states a specific verb and resource: create a file entry and receive upload_url + confirm_url for direct upload. It clearly distinguishes this tool from nukez_confirm and nukez_store by defining its role in the upload flow.

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?

It explicitly says to use this for large files from local/external sources against Cloud Run and gives a concrete alternative: use nukez_store with data_b64 for small inline content under 4KB. It also describes the expected client-side follow-up steps: PUT bytes to upload_url, then call nukez_confirm.

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