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

Annotations already declare destructiveHint=true, openWorldHint=true and idempotentHint=false, and the description adds only that uploads are private and that no local filesystem is available. It never says what a destructive call actually destroys or overwrites (e.g., whether reusing an id replaces existing metadata or an existing asset), and 'recover' sits in unacknowledged tension with idempotentHint=false, which will confuse an agent reasoning about safe retries.

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 short sentences with no filler, and the most surprising constraint (no filesystem access) is front-loaded in the second sentence. It is efficient, though the terseness leaves the complex 12-parameter contract underexplained rather than over-explained.

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 12-parameter, destructive, open-world mutation tool with no output schema and near-zero schema descriptions, the definition is far too thin. It says nothing about what the call returns (upload URL? asset id? session token?), what the caller does next, or how required metadata like sha256/byte_length are derived and validated, leaving the agent unable to invoke it correctly without guessing.

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 only 17% across 12 parameters (9 required), so the description carries the burden — yet it explains none of them. It never mentions sha256, byte_length, media_type, alt_text, caption, provenance, poster_asset_id or idempotency_key, and only vaguely gestures at 'metadata' and separately transferred bytes. The critical detail that the caller must supply a hash and byte length of a file it cannot itself send is nowhere stated.

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 gives a specific verb and resource: it initiates (or resumes) a private, resumable upload session for a typed asset, and it distinguishes itself from a generic file write by stating 'from metadata' and 'file bytes are transferred separately'. What it does not do is name its obvious partner (summer_assets_uploads_complete) or contrast with summer_assets_edit, so an agent still has to infer the start→transfer→complete workflow.

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?

'Start or recover' implies when the tool applies and hints that re-calling returns an existing upload, and 'file bytes are transferred separately' implies a follow-up step exists. But no alternative is named, no prerequisite is stated (company/auth requirements), and the condition that selects complete vs. this call is left implicit.

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