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

With no annotations supplied, the description carries the full behavioral burden, yet 'Rating colour scales' discloses nothing about side effects, authentication, return format, or whether the data is static reference data. It is a bare noun phrase that gives the agent no behavioral information at all.

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?

Three words with no front-loaded verb or scope statement — this is under-specification rather than genuine conciseness. There is no wasted sentence, but the fragment is too small to be useful.

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?

With no annotations, no output schema, and no parameter documentation, the description is the only source of information about this tool, and it fails to say what a 'scale' contains, what domain it applies to (maps, tanks, players), or how the colour values are keyed. Something as simple as 'Returns the static list of rating colour scales used across map and tank ratings' would have closed the gap.

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 schema declares zero parameters at 100% coverage, so there is nothing for the description to document and the baseline of 4 applies. The description neither adds nor detracts from parameter understanding.

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 'Rating colour scales' is essentially a restatement of the tool name with the word 'colour' added, rather than a specific verb+resource statement. It does not distinguish this tool from the many sibling rating tools (maps_ratings, tanks_ratings, ratings_mine, rates), leaving the agent to guess whether it returns colour mappings, thresholds, or scale metadata.

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 when-to-use guidance, no mention of prerequisites, and no naming of alternatives such as rates or ratings_mine. Nothing in the text tells the agent under what circumstances this zero-parameter tool should be preferred over the sibling ratings endpoints.

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