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

Annotations already declare it is a non-destructive, non-idempotent write (readOnlyHint=false, destructiveHint=false). The description adds genuine behavioral value beyond that: it explains the catalog rendering effect and that each variant retains its own page and link, which reassures the agent nothing is lost. It does not mention that repeated calls create new sets (non-idempotency).

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 with the core action and outcome in two tight sentences, followed by a compact arg list. The 'Args:' restatement is mildly redundant with the schema but overall the text earns its place.

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?

An output schema exists, so return values need not be explained. For a multi-design grouping operation the description covers purpose, the 2+ prerequisite, and the visible outcome, leaving only the non-idempotent repeat-call behavior unstated.

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 the schema already documents both parameters. The 'Args:' line restates design_ids and primary without adding syntax, format, or constraint detail beyond what the schema provides; the '?' correctly signals primary is optional. Baseline 3 is appropriate.

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 ('Group my recolours') and resource (a colorway set) and clarifies the outcome ('one card for the set; every variant keeps its own page and link'). It is clear on its own, but it does not name or differentiate itself from related siblings like designer_add_to_colorway or set_colorway_primary.

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 implies usage by stating the prerequisite ('2+ of my designs', 'ONE artwork'), which gives implicit guidance about when the tool applies. However, it never states when NOT to use it or how it differs from the colorway siblings, so usage is inferred rather than directed.

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