prepare_dynain

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

With no annotations, the description carries the full burden and does well: it discloses overwrite behavior (existing dynain.k kept unless overwrite=True), a size cap via LSDYNA_MCP_MAX_DYNAIN_MB with refusal, that rigid-body displacements are not saved, and the double-springback-card hazard. It does not say whether the copy is atomic or what happens if the source dynain is absent or the destination is read-only.

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?

Front-loaded with the step label, verb, and resource, and every sentence carries information. The long parenthetical about Workbench Output Controls is dense and slows parsing, but the content is not wasteful.

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. The description covers the prerequisite step, the destructive/conservation behavior, the size guard, the explicit unsupported data (rigid bodies), and the failure mode to avoid, which is sufficient to call the tool correctly.

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 coverage is 0%, so the description must compensate and largely does: directory is identified as 'the explicit run's working_dir' and overwrite is tied to the keep-or-replace behavior. It does not state path format expectations (absolute vs. relative) for directory, which is the remaining ambiguity.

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 concrete verb and resource ('copy the solver's ASCII dynain file to dynain.k') plus the downstream purpose (External Model import). It implicitly separates itself from the sibling set_dynain_output, which is named as the producer of the ASCII file, and from multi-system transfers that use .lsda directly.

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?

Gives explicit prerequisites ('Get an ASCII dynain with set_dynain_output(psid, fmt="ascii") in the explicit run'), an explicit exclusion ('leave Workbench's own Output Controls > Stress File for flexible parts OFF'), and a when-not-to-use case (multi-system transfers use .lsda directly, no conversion needed).

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