Run-Config Reference

The run-config JSON controls how compiled IR is evaluated — discount rate, as-of date, parameter overrides, named scenarios, and Monte Carlo. Pass it with cfdl run --config run.json, cfdl_sdk.run(config=...), or the API server's config field.

Full shape

{
  "deterministic": {
    "annual_discount_rate": 0.10,
    "as_of": "2026-01-01",
    "parameters": {
      "stream.cre.lease.base_rent:amount": 1000.0
    }
  },
  "scenarios": {
    "stress": {
      "annual_discount_rate": 0.12,
      "parameters": {
        "stream.cre.lease.base_rent:amount": 800.0
      }
    }
  },
  "monte_carlo": {
    "trial_count": 1000,
    "seed": 12345,
    "distributions": {
      "cfg.exit_multiple": { "kind": "normal", "mean": 8.0, "stddev": 1.0 },
      "cfg.growth": { "kind": "uniform", "min": 0.01, "max": 0.05 }
    }
  }
}

Every section is optional; an empty config runs deterministically with the CLI's --rate fallback (default 0.0).

deterministic

• annual_discount_rate — the discount rate for NPV (annual; the engine publishes run.annual_discount_rate and run.periods_per_year back into the metrics).
• as_of — valuation as-of date (YYYY-MM-DD).
• parameters — override map applied before evaluation.

Parameter keys

• stream.<dotted_stream_name>:amount — override a stream's amount.
• cfg.<path> — set a value readable in expressions via cfg.<path>.

scenarios

Named variants of the deterministic run. Each scenario may override the discount rate, as-of date, and parameters; results carry one entry per scenario alongside the base deterministic result.

monte_carlo

• trial_count and seed are required — there are no implicit seeds.
• distributions adds or overrides distributions at run time without touching the model. Supported kinds here: fixed { value }, normal { mean, stddev }, uniform { min, max }.
• In-language assume <x> ~ … distributions (which also include LogNormal and Triangular) are sampled per-trial automatically; the run-config layer is for overrides and experiment knobs.

Each assumption draws from its own deterministic stream derived from the seed — results are byte-reproducible, and adding one assumption never changes another's draws.

Precedence

Run-config values override CLI fallbacks (--rate, --as-of). Scenario values override deterministic values for that scenario only.

Where results land

deterministic.metrics, one scenarios.<name> block per scenario, and monte_carlo.metrics with mean/stdev/min/max and percentiles per metric — see the Results schema.