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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds 'Every call is read-only and idempotent, so after correcting the input it is always safe to retry' and explains error handling: 'never raises a protocol error — it returns {"error": "..."}'. This provides valuable behavioral context beyond the 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 a front-loaded purpose, followed by output format, usage guidelines, error handling, and safety. Every sentence adds value, and there is no redundancy. It is concise given the amount of useful information packed in.

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?

Given the tool's moderate complexity (2 parameters, simple output) and the presence of an output schema, the description covers all necessary aspects: input format, output structure, error handling, usage context, and safety. It is fully self-contained and leaves no gaps for an 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?

Schema description coverage is 100%, so the baseline is 3. The description includes an example usage and notes the delimiter constraint, but it does not add significant new meaning beyond what the schema already provides for the two parameters. The example is helpful but not essential for understanding parameter semantics.

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 starts with 'Profile pasted CSV data column by column with data-quality flags,' which is a specific verb+resource combination. It provides a typical input and output example, and clearly distinguishes from sibling tools by stating what it is not for (ab_test, correlation, growth_rates, forecast_trend).

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?

Explicitly says 'Use as the first look at unfamiliar tabular data' and then lists exclusions: 'Not for testing a hypothesis (ab_test, correlation) and not for time-ordered trends (growth_rates, forecast_trend).' This directly names alternatives and gives clear when-to-use and when-not-to-use guidance.

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