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

Annotations cover safety profile (readOnlyHint=false, destructiveHint=false). Description adds pricing ('FREE') and critical downstream usage ('pass as seedImageAssetId to generate_influencer_look or build_influencer_vault'), which the annotations don't provide. Doesn't describe failure modes for non-stable URLs, keeping it from 5.

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?

Front-loaded purpose, then cost, then prerequisites, then workflow. Every sentence carries useful information. Four sentences with some density but no fluff.

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?

No output schema, but description explicitly states the return value (vault asset id) and how to consume it downstream. Covers prerequisites, cost, and integration path. Nearly complete for a mutation tool.

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%, so baseline 3. Description adds the constraint that imageUrl must be a stable public/hosted URL and that influencerId comes from create_influencer, and describes role via 'identity reference'. Slight value add above 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?

States a specific verb (Attach) and resource (user's own image as identity reference for an influencer). Clearly distinguishes from sibling create_influencer and generate_influencer_look.

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?

Explicitly names import_asset_from_url and create_upload as prerequisite paths depending on source (URL vs raw bytes). Also tells the agent when to skip the paid look preview. Strong routing guidance.

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