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

Annotations already signal read-only safety, and the description adds meaningful behavioral context: the operation costs $0.05 and requires an API key, which is beyond the structured annotations. It also discloses that the output can include a signed_url for download/processing, clarifying a key behavioral detail not present in the schema. No contradiction with the annotations.

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 description is a compact two-sentence definition with no filler. The primary action and resource are front-loaded, and the cost/api-key caveat is appended economically without disrupting the core message.

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?

Given the low parameter count and existing output schema, the description provides the key context needed to call the tool: what it returns, the lookup method, cost, and authentication requirement. It falls slightly short only because it does not clarify the include_signed_url parameter's behavior, which is important for accurate invocation.

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?

With schema description coverage at 0%, the description must carry parameter meaning, but it only explicitly mentions asset_id and the concept of a signed_url. The optional boolean include_signed_url is not named or explained, leaving its effect ambiguous. This is a notable gap for an otherwise simple two-parameter tool.

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 uses a specific verb ('Fetch'), a clear resource ('one asset'), and the lookup key ('asset_id'), making the tool's core purpose unambiguous. It also states the return context ('signed_url for download/processing'), distinguishing it from sibling list-type tools like get_entity_assets or update-oriented tools like update_asset.

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 phrase 'Fetch one asset by asset_id' gives a clear and direct when-to-use scenario: retrieve a single asset when you have its ID. It also adds practical usage conditions, noting the $0.05 cost and API key requirement. However, it does not explicitly name alternatives or exclusion cases, such as when to use get_entity_assets instead.

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