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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is fully covered structurally. The description adds the grading vocabulary (verified/near/partial/divergent), which is real behavioral context, but it doesn't say what determines those grades, that the cutoffs are adjustable via the near_*/verified_* params, or how ties/boundary cases resolve.

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?

A single front-loaded sentence with the action first and the outcome legend compactly parenthesized. Nothing superfluous and nothing buried.

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 12 parameters, nested objects, and 9 grading-threshold knobs, the description is thinner than ideal: it never notes that the default thresholds can be relaxed/tightened, nor how the tool relates to the align/compare siblings that would normally produce the input. An output schema exists, so return-value explanation is legitimately absent, which keeps this at minimum-viable rather than poor.

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 the schema already explains every parameter, including the important 'ungapped identity, NOT gap-inclusive identity' caveat. The description contributes nothing parameter-specific, 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 — grade a sequencing read against a reference from an alignment — and enumerates the four grade outcomes (✓/⚠/~/✗), so the agent knows exactly what the tool produces. It does not, however, distinguish itself from nearby siblings such as compare_reads_to_reference or alignment_agreement, which an agent could plausibly confuse it with.

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 phrase 'from an alignment' implies the prerequisite (pre-gapped read/ref rows) but gives no explicit condition for choosing this over compare_reads_to_reference or alignment_agreement. No when-not guidance and no mention that thresholds are tunable to shift the grade boundaries.

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