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

Annotations already cover the safety profile (readOnly, non-destructive, not open-world), and the description adds genuinely useful behavior: it returns base calls crossed as a record, not the trace signal/peaks, so the agent knows it cannot write raw chromatogram data onward. That is meaningful disclosure beyond the annotations, though it stops short of discussing quality defaults or failure modes.

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?

Four sentences, front-loaded with the read-and-return core, and no wasted preamble. The final 'a record crosses a wire as bases, and a peak cannot be written as one' is slightly ornamental but still conveys the output-type constraint.

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 an output schema present, return-value explanation isn't required, and the description covers what the tool reads, what it emits, and the signal-vs-bases constraint. It's nearly complete for a 6-param nested tool, though it leaves the project/_files/_subject plumbing entirely to the schema.

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 schema already documents trim, min_quality, reverse_complement, document, _files and _subject in detail. The description adds only general framing about trim bounds and quality, no syntax or format detail 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?

States a specific verb (read) and resource (Sanger trace .ab1/.scf/.ztr) plus the exact output shape: base calls as a record with per-base quality and trim bounds. The clause 'The trace SIGNAL stays here' sharply distinguishes it from the signal-returning siblings like trace_raw_signal.

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 says what the output enables (verify against a reference, align, gate on quality), which implies downstream usage, but it never states when to pick load_trace over alternatives such as list_traces, trim_trace, or trace_raw_signal. The usage context is left to inference.

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