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 genuine value by disclosing what the scoring actually produces (four distinct biophysical quantities) and that it operates on pre-existing sequence rather than mutating anything.

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?

Two sentences with zero waste: the first front-loads the verb and enumerates the outputs, the second establishes the read-vs-write boundary against the sibling. Every clause earns its place.

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?

An output schema exists, so return values need not be explained, and the description covers purpose, computation, and sibling differentiation for what is a narrow read-only tool. Nothing an agent needs in order to invoke it correctly is missing.

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 all four parameters (mrna, _files, _subject, start_pos) are already documented, which sets the baseline at 3. The description only adds framing that the scored RBS sits 'in front of a start codon', weakly reinforcing the semantics of start_pos, without adding syntax or format detail beyond the schema.

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 (score) plus resource (ribosome-binding site) and enumerates exactly what is computed: Shine-Dalgarno hybridisation energy, competing mRNA folding, implied spacing, and relative initiation strength. It also explicitly distinguishes itself from the sibling design_rbs by framing this as reading an existing 5'UTR, so an agent can disambiguate without opening either schema.

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?

Names the alternative tool explicitly ('design_rbs writes a new one') and gives the condition that selects this one instead ('reads an existing 5'UTR'). It sets a clear boundary between reading/scoring and writing/designing, leaving no inference needed.

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