Set an image control node by URL

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

Annotations already provide safety hints, but the description adds significant behavioral detail: it validates node type via get_model, checks URL reachability, and supports force bypass. It also explains that validation is default on and mentions the urlCheck return field, giving full transparency beyond 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 well-structured with the main action first, then constraints, then parameter list. It is slightly verbose but every sentence adds value. Could be tightened, but not excessively long.

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 10 parameters and no output schema, the description covers all necessary context: authentication, node identification, validation behavior, force override, and return values. It also explains the limitation of no upload API, providing complete context for the agent.

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 100% schema coverage, baseline is 3, but the description adds strong value: it explains the preference for nodeId over nodeTitle, the interplay of app vs appToken, the effect of validate_url and force, and the response_format options. This goes well beyond the schema definitions.

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 purpose: 'Set an image-type control node to a hosted image URL'. It distinguishes this tool from siblings by specifying it's the only way to place imagery in Singular and explains the need for public URLs, making the intent unambiguous.

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 explains when to use the tool (the only way to set imagery) and provides guidance on validation and force flags. However, it doesn't explicitly mention when not to use it or compare to alternative tools like singular_update_content, though context implies its specific use case.

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