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

Annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false). The description adds real value beyond that: it discloses the two operating modes, the ready=true return signal, and the critical constraint 'Never pass file bytes'. It omits how long a reserved upload lives, auth requirements, and what happens on failure.

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?

Three sentences, front-loaded with the primary file-based mode, which is good structure. But the compression is so aggressive ('reserve an HTTP upload and PUT files before publishing', 'returns ready=true after download') that clarity is sacrificed, so it reads as terse rather than concise.

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 mutating, non-idempotent tool with a nested object parameter, zero schema coverage, and no output schema, the description should do more. It leaves document_id undefined, the nested file fields unexplained, and the lifecycle/expiry of a reserved upload unstated; the only return detail given is ready=true.

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 0%, so the description must carry parameter meaning. It explains `file` indirectly (use a pointer, never bytes) but says nothing about the nested download_url/file_id/file_name/mime_type fields, and `document_id` is not mentioned at all despite being a top-level parameter. This leaves a documented gap rather than compensating for it.

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 conveys a specific verb+resource: staging an HTML attachment as index.html or reserving an HTTP upload to prepare a publish. However, the phrasing is dense and elliptical ('reserve an HTTP upload and PUT files before publishing'), and it never names a sibling or states the obvious relationship to shareout_publish. An agent can roughly infer the purpose but not cleanly distinguish it from the other shareout tools.

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 does give a conditional usage rule: pass `file` to stage an attachment, otherwise reserve an upload, and the 'before publishing' clause implies sequencing relative to shareout_publish. It does not explicitly name an alternative tool or state when-not to use this one, so guidance is implied rather than explicit.

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