Add raw namelist

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

Annotations declare the mutation profile (readOnlyHint=false, idempotentHint=false, destructiveHint=false). The description adds genuine context beyond that: verbatim emission, insertion point (before &TAIL), format validation, and the duplicate-namelist error. Only minor gaps (no statement about how entries are ordered/listed) keep it from a 5.

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?

Three tight sentences, front-loaded with what it does and where the line lands, followed by use cases and exclusions. Dense with useful detail, though the trailing rules-reference line is mild noise.

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?

A single-parameter mutation tool with no output schema is adequately covered: usage conditions, format rules, placement, and error behavior are all present. The remaining gap is lifecycle behavior (ordering of multiple raw lines, interaction with removal) which is minor for a tool this scoped.

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 100% and gives an example, so baseline is 3. The description adds a real constraint not in the schema ('Must start with & and end with /') plus two more concrete examples, which meaningfully improves correct invocation.

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 (add) and resource (raw namelist line), plus the exact placement semantics ('emitted verbatim just before &TAIL'). An agent can distinguish it from siblings like list_raw_namelists and remove_raw_namelist, and the examples of what a namelist line looks like remove all ambiguity.

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?

Explicitly states when to use it ('settings with no GUI dialog') and when not to ('Use the dedicated tools for anything the GUI does model' with the full list of modeled namelists). It even names the failure condition for misuse (a duplicate namelist is an FDS error), so routing is unambiguous.

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