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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds genuinely useful behavior beyond that: a 15-minute expiry window, that the response carries private request headers, and the security-critical warning that both values are credentials scoped to that one file. It stops short of stating permission requirements or what happens on repeat calls.

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 tight sentences, front-loaded with what the tool produces and what it returns, with zero filler. The closing sentence is short but carries a real security constraint rather than padding.

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 no output schema, the description carries the return-value burden and does it well: it names both the header-bearing URL and the browser-ready downloadUrl. Missing only edge context such as required permissions or behavior when the asset is unavailable, which keeps it from a 5.

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% — both workspaceId and assetId are fully documented in the schema, including the sourcing hint for assetId. The description adds no parameter-level detail, so the baseline 3 applies.

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?

States a specific verb and resource — 'Prepares a 15-minute private download of one stored asset’s original file' — and immediately distinguishes itself from metadata-oriented siblings like fuzz_get_asset by returning a fetchable URL plus headers. An agent knows exactly what it gets without opening the schema.

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?

Usage is implied by the purpose ('download one stored asset'), but there is no explicit when/when-not guidance and no reference to alternatives such as fuzz_preview_assets or fuzz_get_asset. An agent can infer the use case but is not told when this is the right choice over a sibling.

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