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

Goes well beyond the annotations (readOnly=false, openWorld=false, destructive=false) by disclosing the returned identifiers, the one-hour expiry on upload_url, the required zip layout, the exact upload mechanism, quota behavior, and the embedded-game network/host restrictions. These are exactly the operational traits an agent cannot infer from structured fields.

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 return contract before the procedural details, and the dense clause chain is mostly load-bearing. It is long for a single-parameter tool, and the wrapper/network-host warnings sit at the tail, but nothing is pure padding.

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?

With no output schema, the description still names what comes back (build_id, upload_url, asset_base) and supplies the full end-to-end procedure and constraints, so an agent can both call it and complete the flow correctly.

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% and the sole parameter (title_id) is already documented as the live TitleID versus the -DEV copy. The description adds only the framing that the target is a 'Title', so the baseline of 3 applies — the schema does the heavy lifting.

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 (start uploading), resource (a READY web build of the game), and destination (a Title), immediately distinguishing it from finish_build_upload. An agent knows this is the initiation step of a two-phase upload flow 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?

Explicitly sequences the follow-up (call finish_build_upload after the PUT) and states a hard prerequisite: 'Needs a shell to run the upload — a browser-only client cannot upload files.' It also warns against uploading a wrapper rather than the game itself. It stops short of enumerating alternative tool choices beyond the successor step.

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