Analyze content-performance patterns

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

The annotations already declare readOnlyHint, idempotentHint, and destructiveHint, covering the safety profile. The description adds the data requirement (at least three measured posts), which is a useful behavioral constraint beyond annotations. No contradiction. However, it does not state what happens if the requirement is unmet or the return format, so not a 5.

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 that front-loads the core action ('Calculate correlations') and includes a necessary constraint in a compact manner. No redundant wording.

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 output schema, the description should at least hint at the return value. It says 'Calculate correlations' but doesn't specify the output structure or behavior when the precondition is not met. However, the tool has a small parameter surface and annotations, making it moderately complete.

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 has one required parameter, 'metric', with an enum of four performance metrics, but schema description coverage is 0%. The description does not mention this parameter at all; it only says 'performance' generically. This fails to compensate for the lack of schema descriptions, leaving the agent to infer the mapping between the parameter and the analysis.

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 verb 'Calculate' and specifies the resource as 'correlations between performance and word count, title length, and UTC send hour.' This clearly states what the tool does and distinguishes it from siblings like get_post_performance or compare_posts by focusing on multi-factor pattern analysis. It also includes a requirement, further clarifying scope.

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 provides a clear precondition ('Requires at least three measured posts') which indicates when the tool is applicable, but does not explicitly compare to siblings or mention when not to use it. This gives clear context without exclusions, so a 4.

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