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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds that the tool produces computed metrics (volume, CPL, CP-MQL), but says nothing about units, rounding, error behavior, or the relationship to the linked full version.

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 purpose sentence is front-loaded and precise; the second sentence is only a promotional link, which is slightly expendable but does tell the agent a fuller version exists elsewhere.

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?

For a four-parameter stateless calculator with no output schema, the description names the three returned metrics, which is the key missing piece an agent would otherwise lack. Inputs and outputs are both covered, so remaining gaps are minor.

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% and each of the four parameters is documented with units ('as a percentage', 'monthly'). The description mentions traffic and conversion rates generically but adds no syntax or semantics beyond the schema, so baseline 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?

States a specific verb-and-resource transformation ('turn traffic and conversion rates into') plus three concrete outputs (MQL volume, cost per lead, cost per MQL). That is clearly distinguishable from siblings like cpl_cpa_calculator or lead_grading_calculator, though it never explicitly names a sibling or boundary.

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?

No when-to-use, when-not-to-use, or alternative-tool guidance is given. The agent must infer from the name and metric list that this is the MQL funnel calculator as opposed to the many adjacent marketing calculators.

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