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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds the crucial non-obvious fact that the tool only returns instructions and performs no action — the single most important behavioral disclosure for a tool named 'set' — but does not describe the shape or length of the returned guidance.

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 core message (returns instructions, executes nothing) is front-loaded, but the sentence is awkwardly constructed and the trailing 'Brandfolder's official API: Yes' is noise for a tool that performs no API call.

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 zero-parameter, no-output-schema guidance tool with full annotation coverage, the definition supplies the essentials: what it returns, that it has no side effects, and which sibling tools finish the job. Minor gaps remain on return format and how to phrase the follow-up browser steps.

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 tool takes zero parameters, so the baseline is 4. The description correctly implies no inputs are needed, though it could have noted that details like which custom field to set must be conveyed in the follow-up browser actions.

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 concrete deliverable — step-by-step instructions (screens, buttons, fields) for setting a custom field in Brandfolder — and clarifies the otherwise misleading name by saying it 'opens nothing by itself.' It distinguishes itself from the cotlet_browser_* siblings by framing them as the execution step, though the 'set_custom_field' name still implies mutation that the tool does not perform.

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?

It gives a clear workflow: call this first for guidance, then perform the action with cotlet_browser_* in the user's Cloud Browser. There are no explicit exclusions (e.g., when to skip this and act directly), which keeps it short of a 5.

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