Model Benchmark
The AI CLI's accuracy is measured — not assumed — by a dedicated benchmark: 100 tasks in three complexity tiers, judged through layered verdict gates up to real job execution against Dockerized data sources, across 7 mainstream LLMs. This page summarizes the methodology, the results, and what they mean for choosing a model.
Results below were measured in July 2026 against seatunnel-cli v0.1.0 (commit
59ada4ec0) with models served by AWS Bedrock. Accuracy drifts as models and the CLI evolve; treat the numbers as a snapshot and re-run the benchmark for current values.
Methodology
Task suite: 100 tasks — 20 simple (single source→sink), 45 medium (type mapping, CDC, transform chains, multi-table), 35 complex (multi-source DAGs, fan-out, conditional routing) — across 12 ETL scenario categories, with 10 Chinese-language prompts and 18 rule probes targeting known LLM failure modes (conditional option misuse, BATCH/STREAMING inference, routing-label wiring).
Verdict gates, mirroring the CLI's own check → dry-run → run pipeline:
| Gate | Verdict | Catches |
|---|---|---|
| L1 static | HOCON parse + connector metadata + assertions | Syntax, wrong connector, missing options |
| L3 real execution | Job runs on the official apache/seatunnel image against real MySQL/PostgreSQL/Kafka/ClickHouse/Elasticsearch; batch = exit code, streaming = 60s health | Everything "looks right but doesn't run" |
Repair loop: on failure, the failing gate's real error output is fed to the CLI's own repair agent, up to 3 rounds. All verdicts are deterministic — no LLM-as-judge.
Headline Result: Static Rankings Invert Under Real Execution
| Model | Static gate (L1) | Real execution (L1+L3) |
|---|---|---|
| Claude Opus 4.8 | 89% (rank 3) | 85% (rank 1) |
| GPT-5.6 Sol | 90% (rank 2) | 81% (rank 2) |
| GPT-5.6 Terra | 93% (rank 1) | 74% (rank 3) |
The static leader wrote configs that looked correct but failed at runtime (−20pp static→real decay); the static #3 wrote configs that ran (−6pp decay). "Looks correct" and "actually runs" are different model capabilities — which is why this benchmark executes configs for real, and why accuracy claims based on static checks alone should be treated with caution.
Full Static-Gate Ranking (7 models)
| Model | Pass (≤5 repairs) | First-try pass | Repaired |
|---|---|---|---|
| GPT-5.6 Terra | 93% | 79% | +14 |
| GPT-5.6 Sol | 90% | 80% | +10 |
| Claude Opus 4.8 | 89% | 87% | +2 |
| Claude Sonnet 5 | 82% | 78% | +4 |
| Claude Fable 5 | 80% | 73% | +7 |
| Qwen3-Coder-Next | 67% | 53% | +14 |
| DeepSeek V3.2 | 58% | 58% | +0 |
Model Behavior Profiles
Generation ability and repair ability are independent dimensions — and family traits are consistent:
- First-try-correct (Anthropic family): Opus 4.8 has the highest first-try rate (87% static / 77% real) and the smallest static→real decay — what it writes tends to run. But its repair contribution is minimal (+2): it rarely recovers from its own failures.
- Iterative-repair (GPT-5.6 Terra): unremarkable first-try, but the strongest repairer — it fixed 48% of its real runtime failures, climbing from 55% to 74%. Its drafts carry the most "looks-right-but-won't-run" risk.
- Repair-disabled (DeepSeek V3.2): zero successful repairs in 100 tasks — its repair attempts return the original config or give up. With a product built around an auto-repair loop, this effectively halves the product's mechanism.
- Notable: the deep-reasoning flagship (Fable 5) ranked only 5th — it over-asks clarifying questions where the task calls for sensible defaults. And on the 10 Chinese-language tasks the Chinese-developed models scored lower (Qwen 5/10, DeepSeek 4/10) than GPT-5.6 Sol (10/10).
Model Selection Guide
| Scenario | Recommendation | Why |
|---|---|---|
| Interactive use (user waiting) | GPT-5.6 Sol / Terra | Fast (25–58s/task), high combined accuracy |
| Unattended / batch generation | Claude Opus 4.8 | Highest first-try rate; output most likely to run unmodified |
| Budget-sensitive regression runs | Qwen3-Coder-Next | Lowest cost tier; acceptable for smoke testing, not production generation |
| Avoid for auto-repair workflows | DeepSeek V3.2 | Repair success rate of zero in measurement |
Known Weak Scenarios (all models)
Thirteen tasks failed for every top-3 model. If your pipeline matches one of these shapes, review the generated config before production use:
| Scenario | Failure root cause |
|---|---|
| Doris / StarRocks sinks | Connector option knowledge gaps (fenodes, load ports, save modes) |
| PostgreSQL-CDC | Missing prerequisites (replication slots, publications) not reflected in config |
| Conditional routing (one source split to multiple sinks by predicate) | plugin_output/plugin_input wiring with parallel SQL transforms |
| Wide DAGs (5+ blocks, mixed transforms) | Label pairing and block-ordering mistakes |
These clusters are engineering targets, not permanent limits: they are being addressed through connector-metadata injection and golden-example coverage, with improvements verified against this same benchmark.
Repair Loop: Measured Effectiveness
Feeding real engine errors back to the repair agent recovered 47% of runtime failures (top-3 models combined). The same model repairs structured validation errors at ~2× the rate of raw Java stack traces — evidence that structured error parsing, not a smarter model, is the highest-leverage next improvement for the repair loop.