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

Annotations cover the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=false), and the description adds genuine method context beyond that: the two solvers and their cost tradeoff, the exact Tm model (Biopython Tm_NN over Allawi & SantaLucia 1997 DNA_NN3). It does not quantify run cost or failure modes in detail, but the algorithmic disclosure is meaningful.

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 core behavior is front-loaded in the first sentence, followed by two supporting sentences on solvers and Tm method. It is appropriately brief for a 47-parameter tool, though the trailing fragment 'A design/write.' is awkward and adds nothing beyond the write annotation.

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 very complex design tool an output schema exists, so return values need not be explained, and 100% schema coverage handles the parameter surface. The description supplies the essential model-level context (shared overlap constraint, solver choice, Tm method), leaving only prerequisites such as the open-plasmid/flanking requirement 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% across 47 parameters, so the schema already documents every argument in depth. The description only gestures at the salt/buffer parameters ('under the salt correction and buffer below') without adding syntax or defaults, so the 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 precise verb+resource ('Design site-saturation mutagenesis (SSM) primers') and adds the defining structural signature — one overlapping forward/reverse pair per site sharing a single reaction-level overlap and 3' temperature. This implicitly separates it from siblings like design_mutagenesis_primers and design_multisite_primers, but no sibling is named explicitly, so it falls short of a full 5.

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 scope ('every site amplifies in the same tube') implies when this tool is appropriate versus simpler single-site designs, and it notes the default solver is fast with exhaustive 'on request'. However, there is no explicit when-to-use/when-not guidance and no named alternatives, so usage must be inferred.

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