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

No annotations exist, so the description carries the full burden. It does add real behavioral guidance (preserve the manifest, verify hashes, do not declare completion early), but says nothing about what happens when the part is missing, whether retrieval is idempotent, or any auth/rate constraints.

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 tight sentences with the core action front-loaded and the verification caveats following. Nothing is redundant, though the second sentence mixes two distinct instructions and could be split for clarity.

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?

With four undocumented required parameters, no annotations, and no output schema, the description should compensate but does not — it never explains the return value, error conditions, or the meaning of the identifiers. An agent can infer the high-level intent but not how to call it correctly.

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% across four required parameters, and the description explains none of them. 'From your session' loosely gestures at session_id and 'part' at index, but export_id, request_id, index ranges, and the 64-hex pattern are left entirely to the raw schema.

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 names a specific verb and resource ('Retrieve one existing resumable export part') and scopes it to the caller's session, which separates it from get_result and get_status at a glance. It stops short of explicitly contrasting itself with those siblings, so it is clear but not maximally differentiated.

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?

'Without inference' and 'do not claim completion until all parts are received' imply a polling/assembly workflow, but the description never states when to call this versus get_result, get_status, or export_offer. Usage is implied rather than spelled out.

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