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

Annotations already declare the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false), so the description has a lower burden. It adds that the result is a pre-signed upload URL, which is useful, but it does not disclose URL expiration, single-use behavior, or how the URL relates to the multipart upload sequence.

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 definition is a single front-loaded sentence with no wasted elaboration. The phrase 'Use this endpoint to' is mild boilerplate, but the description remains efficiently structured.

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?

An output schema exists, so return values need not be explained, and the input schema covers both required parameters. However, the description omits the multipart-upload workflow context needed to place this call correctly among many sibling tools.

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%, so the schema already documents asset_id and part_number. The description only mentions the given part number and adds no syntax, format, or meaning beyond what the schema provides. Baseline 3 is appropriate when 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?

The description states a clear verb and resource: retrieving a pre-signed upload URL for a given part number. It does not name or distinguish itself from related multipart-upload siblings such as multipart_upload_list or complete_multipart_upload, so sibling differentiation is missing.

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 says to use this endpoint for a given part number, but gives no when-to-use guidance, prerequisites, or comparison to alternatives. An agent cannot tell from this description when retrieve_part_url should be called relative to the other multipart-upload tools.

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