Path lexical relative

path-lexical-relative · version 1.0.0 · File paths (lexical) · free, no key needed

Compute the lexical relative path from one path to another without filesystem access.

Use when you need to: path relative · relative path · compute relative path from to.

Supported

• path relative
• relative path
• compute relative path from to

Not supported

• stat file
• resolve symlinks
• filesystem access
• cross-drive relative path

Behavior

• Compute relative path from "from" to "to" using lexicalRelative.
• same: true if from and to normalize to the same path.
• Cross-drive Windows paths and absolute/relative mismatches throw badInput.
• relative is empty string "" when from and to are same (same:true).

Input

• from (string, required): min length 1; max length 4096
• to (string, required): min length 1; max length 4096
• format (one of "posix", "windows", "auto", optional)

Output

• relative (string, required)
• format (one of "posix", "windows", required)
• same (boolean, required)

Limits

• max path bytes: 4096

Example

Request input:

{
  "from": "/a/b",
  "to": "/a/c/d"
}

Response:

{
  "result": {
    "relative": "../c/d",
    "format": "posix",
    "same": false
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "path-lexical-relative",
  "version": "1.0.0",
  "input": {
    "from": "/a/b",
    "to": "/a/c/d"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/path-lexical-relative/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"from":"/a/b","to":"/a/c/d"}'

The machine-readable contract is at /v1/tools/path-lexical-relative/versions/1.0.0.

CLI

node cli.mjs run path-lexical-relative 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

Related tools

• Path lexical sanitize: Sanitize an untrusted path to produce a safe relative path, stripping roots, drive letters, traversal segments, and illegal characters.
• Path set hierarchy tree: Transform a flat array of file paths into a nested deterministic directory tree structure.
• Path format convert: Convert file paths between POSIX and Windows formats, handling slashes, drive letters, and roots lexically.
• Path lexical common ancestor: Compute the deepest common ancestor directory of a set of paths.
• Path lexical contains: Check whether a child path is lexically inside a parent directory.
• Path lexical join: Join an array of path segments lexically, resolving absolute reset boundaries and normalizing separators.