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

Beyond the minimal annotations, the description discloses content-hashing/deduplication, workspace-owned URL output, direct renderer consumption, and strict format/size limits. This gives the agent meaningful behavioral expectations that annotations alone do not provide.

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?

Five compact sentences deliver the core action, output, usage context, format limits, and deduplication behavior with no redundancy. The most important fact (what the tool stores and returns) appears immediately.

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?

The description, combined with fully documented parameters and an output schema, covers the essential invocation details: accepted input forms, limits, and where the result belongs. It omits edge cases like passing both url and base64, but the schema already hints at the either/or relationship.

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 coverage is 100%, so the baseline is 3, but the description adds value by clarifying the url/base64 mutual-exclusion and the practical format and size constraints that apply to media bytes. This goes beyond mere restatement of parameter names.

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 states a specific verb/resource: storing a photo or video from https or base64. It also situates the tool within the workflow by noting the returned URL goes into film-body media slots, distinguishing it from sibling upload/render tools.

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 description gives clear context for when to use the tool — preparing media for a film body — and even points to describe_film for slot names. It does not explicitly name sibling tools like upload_product_screen or render_asset to state when not to use them, so it misses full exclusion guidance.

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