Context cost

Skill: /context-cost

Model preference: #lowcost

Report how much context overhead the harness will auto-load for a given path — walking up the directory tree and collecting every CLAUDE.md, CLAUDE.local.md, agents.md, and @-import file pulled in at session start.

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Arguments

/context-cost [path]

• path — optional; defaults to the current working directory if omitted.

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Step-by-step execution

Step 1 — Locate the script

Find context_cost.py in the bin/ directory of the SAILL repo. If you are running from within a tested_implementation directory, the script is at ../../bin/context_cost.py relative to your working directory. If running from the repo root, it is at bin/context_cost.py.

Run:

python <path-to-bin>/context_cost.py <target-path> --json

If the script is not found, report its expected location and stop.

Step 2 — Parse and format the output

The JSON structure is:

{
  "path": "...",
  "files": [
    {"level": N, "path": "...", "kb": N, "words": N, "tokens": N, "imported_by": "..." or null}
  ],
  "total_kb": N,
  "total_words": N,
  "total_tokens": N
}

Step 3 — Present the report

3.1 Print: Context overhead for: <path>

3.2 Print a table sorted by level (outermost first):

Level  File                              KB     Words   ~Tokens
-----  --------------------------------  -----  ------  -------
  0    CLAUDE.md                         1.2    210     280
  1    agents.md                         3.4    580     775
       (imported by CLAUDE.md)

Show (imported by <basename>) on a sub-line when imported_by is non-null.

3.3 Print totals:

Total: N files — X.X KB — Y words — ~Z tokens

3.4 Threshold flags:

• If total_tokens >= 20000: [WARN] High context load: ~Z tokens. Consider trimming @-imports.
• Else if total_tokens >= 8000: [NOTE] Moderate context load: ~Z tokens. Worth reviewing.
• Otherwise: no flag.