s3_put_object

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It only states 'Upload', but does not disclose whether the operation overwrites existing objects, requires a pre-existing bucket, or involves any authentication or rate limits. The description adds minimal behavioral context beyond the action itself.

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 a single, concise sentence that directly states the action and target. It contains no unnecessary words or repetition, making it highly efficient and easy to parse.

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 schema is well-documented and the tool is a straightforward S3 PUT operation. The description is adequate but lacks behavioral notes such as overwrite behavior or the need for an existing bucket. For a simple upload in LocalStack, it is minimally viable but not fully comprehensive.

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 input schema provides 100% coverage for all 4 parameters with clear descriptions. The description adds only a slight hint that the body can be 'text or JSON', but this does not go beyond what the schema already conveys about the body being a string. No additional parameter-level semantics are provided.

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 uses the specific verb 'Upload' and identifies the resource as 'a text or JSON object to an S3 bucket', making the tool's function immediately clear. It also distinguishes from sibling S3 operations like s3_get_object and s3_delete_object by focusing solely on the write/upload action.

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 description implies the tool should be used for uploading objects to S3, which is a clear context. However, it does not explicitly state when to use this tool instead of other S3 operations (e.g., get, delete, list), nor does it mention any exclusions or prerequisites such as bucket existence.

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