engine_files_add

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

With no annotations, the description carries the full behavioral burden. It discloses useful details: kind_key defaults to kBase and is checked against the key_value registry, and the engine automatically fills id, name, folder, and row. However, it omits side effects, return values, error behavior, and any authorization or validation requirements.

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 compact and front-loaded with the core purpose. The entity list is long but directly relevant. Each sentence adds useful information, and there is minimal 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?

For a tool with no annotations and no output schema, the description gives enough to construct a basic call, but it does not describe expected return values, error cases, or authentication constraints. The note about MaxFileSize packing is useful but leaves the overall invocation context incomplete.

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?

The description compensates for the low schema coverage by explaining entity, elem_id, file, and kind_key meanings, including the allowed entity list and the kind_key default. It does not mention real_name, but the schema itself provides a description for that field.

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 clearly states the tool's function: 'Attach local files to store elements.' It names the resource type and provides a specific verb, and it is distinct from sibling tools like engine_files_load and engine_files_remove, though it does not explicitly name alternatives.

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?

There is no guidance about when to use this tool versus alternatives, no exclusions, and no mention of prerequisites. The description explains what the tool does but not under what circumstances an agent should choose it over similar tools.

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