The adapters parsed each vendor's proprietary JSON stream (Claude json,
Codex JSONL, Gemini stream-json) to extract tokens/tool-calls, and a
per-model pricing table turned tokens into cost. That coupling was the
brittle hardcoding GStack 2 exists to avoid — it broke every time a vendor
reshuffled its output, and it duplicated what any tool that instruments the
real model call already does. Braintrust owns scoring; it can't see a CLI
subprocess's tokens anyway, so computing cost ourselves meant maintaining
both a parser and a price table forever.
Now each adapter runs the CLI in plain-text mode and returns stdout. Scoring
is unchanged (Braintrust reads the text). RunResult drops tokens/toolCalls;
the comparison table drops the Tokens/Cost columns. Deletes pricing.ts, all
three JSON parsers, and the Gemini stream-schema parser + its test. Gemini
auth detection (env/OAuth/.env) is kept — that's not schema parsing.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Braintrust now owns benchmark scoring, experiments, comparison, and
reporting. GStack keeps only the CLI-agent adapters (the unavoidable shim)
plus operational metrics the CLIs report. runProviderBenchmark wraps each
adapter as a Braintrust Eval task; a deterministic required-terms scorer
replaces the in-house evaluation logic and the optional autoevals ClosedQA
judge replaces judge.ts.
Runs local by default under bun: with no BRAINTRUST_API_KEY it sets
noSendLogs and ships nothing; setting the key opts into the cloud dashboard.
An empty output with zero tokens is thrown so a silent auth/CLI failure
can't masquerade as a 0.0 score.
Deletes runner.ts and judge.ts (and their test-helper re-export shims);
rewires bin/gstack-model-benchmark and adapts the benchmark tests.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
