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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds one genuinely useful behavioral fact — that scoring uses measured empirical ligation data rather than a heuristic — but says nothing about what happens with unmatched or duplicate overhangs, or how 'remedies' alters the run.

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?

One front-loaded sentence with no filler, hedging, or redundant restatement of the title or schema. Every word carries information.

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 values need not be explained, and annotations carry the safety profile. However, for a 7-parameter tool with nested record objects and a remedies side-computation, the description never signals the design→score workflow or the cheap-run tradeoff, leaving meaningful context gaps for such complexity.

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% (including a fully enumerated dataset list and the note that enzyme only applies when dataset is not given), so the baseline of 3 is appropriate. The description adds no parameter meaning of its own, and its emphasis on 'T4 DNA ligase' sits awkwardly beside a dataset enum dominated by Type-IIS enzyme matrices.

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+resource pair: 'Score a Golden Gate junction (fusion-site) set', with the alias 'fusion-site' clarifying terminology. The scoring basis ('against MEASURED T4 DNA ligase end-joining data') separates it from design_overhang_set, check_golden_gate_parts and golden_gate_assemble, but no sibling is named explicitly and the T4-only framing understates that the tool also scores Type-IIS enzyme matrices.

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?

There is no when-to-use guidance, no statement of prerequisites (e.g. that you should already have an overhang set from design_overhang_set or golden_gate_assemble), and no named alternative for related questions such as part-level checks. Usage is only inferable from the single purpose sentence.

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