Locate every Fortran routine that uses a given unit number, with the file each targets. Filter by open, read, or write operations for precise source analysis.
Routines using a Fortran unit number, and the file each use targets. Optionally filter by operation. Exhaustive, not truncated.
| Name | Required | Description | Default |
|---|---|---|---|
| op | No | Optional: open, read, or write | |
| unit | Yes | Unit number, e.g. 107 |
Changes observed during successful MCP inspections.
v0.1.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden. It usefully adds 'Exhaustive, not truncated' and describes the returned relationship (routine to targeted file), but it does not explicitly state read-only behavior, output shape, or any costs or limits. It is adequate but not richly transparent.
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 short clauses, no filler, and the key constraint 'Exhaustive, not truncated' is included without extra words. Every sentence 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?
For a simple two-parameter lookup with no output schema, the description conveys what will be returned (routines and file targets) and the optional filter. It could be slightly fuller about what 'targets' means and any empty-result behavior, but it is close to complete.
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 structured fields already document unit and op; the description only restates that op is optional. No additional format, constraints, or edge-case meaning is provided 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?
The description identifies the resource (a Fortran unit number) and the result (routines using it and the file each targets), so the agent can infer this is a lookup tool. It lacks an explicit imperative verb like 'List' or 'Find', and it does not differentiate itself from sibling tools such as file_io.
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 phrasing 'Routines using a Fortran unit number' implies the tool is for unit-number-based lookup, and 'Optionally filter by operation' gives a usage tweak. It never states when to prefer this over file_io or related siblings, nor gives any exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.