Upload one raw file chunk

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

The description discloses that the tool performs a write at a byte offset and explains why it exists, which adds context beyond the annotations. However, it does not mention potential overwrite behavior, prerequisites such as an existing remote file, error handling, or what a successful chunk write returns.

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 concise sentences, with the core action front-loaded followed by the motivating use case. Every clause earns its place and there is no redundant filler.

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 chunked write operation with no output schema and minimal annotations, the description leaves out critical operational guidance: chunk size limits, ordering/parallelism expectations, whether partial writes are resumable, offset alignment, and success/failure semantics. It explains the why but not enough of the how for an agent to invoke it reliably.

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?

With an empty input schema, the description's reference to a 'supplied byte offset' and 'raw request body' adds some semantic meaning. However, it never names the actual parameters or specifies how the offset is supplied, leaving an agent without sufficient invocation details. The zero-parameter baseline helps, but the description's references to implicit inputs create ambiguity.

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 clearly states the action ('Upload one raw file chunk') and the mechanism ('Writes a raw request body to the remote file at the supplied byte offset'), which is specific enough to distinguish it from ordinary file writes. It even hints at differentiation from multipart uploads by mentioning the 2GB FormData limit, though it does not explicitly name the sibling alternatives.

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?

The phrase 'allowing browser clients to avoid multipart/FormData 2GB limits' gives a clear context and motivation for using this tool. It does not explicitly state when not to use it or name alternatives, but the intended scenario is reasonably clear.

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