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

No annotations are provided, so the description must fully disclose behavior. It states the core action (compare side-by-side on all key metrics) but does not explain what 'all key metrics' includes, the output format, handling of invalid codes, or any limitations. This is minimal disclosure without meaningful behavioral detail.

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 a single sentence, directly phrased, front-loaded with the core purpose, and contains no wasted words. It is appropriately concise for a simple tool.

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?

The tool has no output schema and no annotations, so the description should explain what the agent will receive (e.g., a table of metrics, which metrics, or any caveats). It only says 'all key metrics,' which is vague. Given the tool's simplicity and complete schema, some context is present, but the lack of return-value description makes it 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?

Schema coverage is 100% for the single parameter scheme_codes, which already describes it as an array of 2–10 AMFI code strings. The description repeats the range ('2–10 funds') but adds no additional meaning beyond the schema, so the baseline of 3 applies.

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 uses the specific verb 'Compare' with a clear resource ('funds') and scope ('2–10 funds side-by-side on all key metrics'). It clearly distinguishes from siblings like get_fund (single fund), get_metrics (single fund metrics), and screen_funds (filtering).

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 use when comparing multiple funds, but provides no explicit guidance on when not to use it or alternatives (e.g., 'for a single fund use get_fund'). It lacks the explicit differentiation seen in higher-scoring examples.

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