The open-source behavior regression gate for AI agents.
Think Playwright, but for tool-calling and multi-turn AI agents.
Your agent can still return 200 and be wrong. A model or provider update can change tool choice, skip a clarification, or degrade output quality without changing your code or breaking a health check. EvalView catches those silent regressions before users do.
Traditional tests tell you if your agent is up. EvalView tells you if it still behaves correctly. It tracks drift across outputs, tools, model IDs, and runtime fingerprints, so you can tell "the provider changed" from "my system regressed."
demo.mp4
30-second live demo.
Most eval tools stop at detect and compare. EvalView helps you classify changes, inspect drift, and auto-heal the safe cases.
- Catch silent regressions that normal tests miss
- Separate provider/model drift from real system regressions
- Auto-heal flaky failures with retries, review gates, and audit logs
✓ login-flow PASSED
⚠ refund-request TOOLS_CHANGED
- lookup_order → check_policy → process_refund
+ lookup_order → check_policy → process_refund → escalate_to_human
✗ billing-dispute REGRESSION -30 pts
Score: 85 → 55 Output similarity: 35%
pip install evalviewevalview init # Detect agent, auto-configure profile + starter suite
evalview snapshot # Save current behavior as baseline
evalview check # Catch regressions after every changeThat's it. Three commands to regression-test any AI agent. init auto-detects your agent type (chat, tool-use, multi-step, RAG, coding) and configures the right evaluators, thresholds, and assertions.
Other install methods
curl -fsSL https://raw.githubusercontent.com/hidai25/eval-view/main/install.sh | bashNo agent yet? Try the demo
evalview demo # See regression detection live (~30 seconds, no API key)Or clone a real working agent with built-in tests:
git clone https://github.com/hidai25/evalview-support-automation-template
cd evalview-support-automation-template
make runMore entry paths
evalview generate --agent http://localhost:8000 # Generate tests from a live agent
evalview capture --agent http://localhost:8000/invoke # Capture real user flows (runs assertion wizard after)
evalview capture --agent http://localhost:8000/invoke --multi-turn # Multi-turn conversation as one test
evalview generate --from-log traffic.jsonl # Generate from existing logs
evalview init --profile rag # Override auto-detected agent profileUse LangSmith for observability. Use Braintrust for scoring. Use EvalView for regression gating.
| LangSmith | Braintrust | Promptfoo | EvalView | |
|---|---|---|---|---|
| Primary focus | Observability | Scoring | Prompt comparison | Regression detection |
| Tool call + parameter diffing | — | — | — | Yes |
| Golden baseline regression | — | Manual | — | Automatic |
| Silent model change detection | — | — | — | Yes |
| Auto-heal (retry + variant proposal) | — | — | — | Yes |
| PR comments with alerts | — | — | — | Cost, latency, model change |
| Works without API keys | No | No | Partial | Yes |
| Production monitoring | Tracing | — | — | Check loop + Slack |
| Status | Meaning | Action |
|---|---|---|
| ✅ PASSED | Behavior matches baseline | Ship with confidence |
| Different tools called | Review the diff | |
| Same tools, output shifted | Review the diff | |
| ❌ REGRESSION | Score dropped significantly | Fix before shipping |
EvalView does more than compare model_id.
- Declared model change: adapter-reported model changed from baseline
- Runtime fingerprint change: observed model labels in the trace changed, even when the top-level model name is missing
- Coordinated drift: multiple tests shift together in the same check run, which often points to a silent provider rollout or runtime change
When detected, evalview check surfaces a run-level signal with a classification (declared or suspected), confidence level, and evidence from fingerprints, retries, and affected tests.
If the new behavior is correct, rerun evalview snapshot to accept the updated baseline.
Four scoring layers — the first two are free and offline:
| Layer | What it checks | Cost |
|---|---|---|
| Tool calls + sequence | Exact tool names, order, parameters | Free |
| Code-based checks | Regex, JSON schema, contains/not_contains | Free |
| Semantic similarity | Output meaning via embeddings | ~$0.00004/test |
| LLM-as-judge | Output quality scored by LLM (GPT, Claude, Gemini, DeepSeek, Ollama) | ~$0.01/test |
Score Breakdown
Tools 100% ×30% Output 42/100 ×50% Sequence ✓ ×20% = 54/100
↑ tools were fine ↑ this is the problem
Block broken agents in every PR. One step — PR comments, artifacts, and job summary are automatic.
# .github/workflows/evalview.yml — copy this, add your secret, done
name: EvalView Agent Check
on: [pull_request, push]
jobs:
agent-check:
runs-on: ubuntu-latest
permissions:
pull-requests: write
steps:
- uses: actions/checkout@v4
- name: Check for agent regressions
uses: hidai25/eval-view@main
with:
openai-api-key: ${{ secrets.OPENAI_API_KEY }}What lands on your PR
## ✅ EvalView: PASSED
| Metric | Value |
|--------|-------|
| Tests | 5/5 unchanged (100%) |
---
*Generated by EvalView*
When something breaks:
## ❌ EvalView: REGRESSION
> **Alerts**
> - 💸 Cost spike: $0.02 → $0.08 (+300%)
> - 🤖 Model changed: gpt-5.4 → gpt-5.4-mini
| Metric | Value |
|--------|-------|
| Tests | 3/5 unchanged (60%) |
| Regressions | 1 |
| Tools Changed | 1 |
### Changes from Baseline
- ❌ **search-flow**: score -15.0, 1 tool change(s)
- ⚠️ **create-flow**: 1 tool change(s)
Common options: strict: 'true' | fail-on: 'REGRESSION,TOOLS_CHANGED' | mode: 'run' | filter: 'my-test'
Also works with pre-push hooks (evalview install-hooks) and status badges (evalview badge).
Leave it running while you code. Every file save triggers a regression check.
evalview watch # Watch current dir, check on change
evalview watch --quick # No LLM judge — $0, sub-second
evalview watch --test "refund-flow" # Only check one test╭─────────────────────────── EvalView Watch ────────────────────────────╮
│ Watching . │
│ Tests all in tests/ │
│ Mode quick (no judge, $0) │
╰───────────────────────────────────────────────────────────────────────╯
14:32:07 Change detected: src/agent.py
╭──────────────────────────── Scorecard ────────────────────────────────╮
│ ████████████████████░░░░ 4 passed · 1 tools changed · 0 regressions │
╰───────────────────────────────────────────────────────────────────────╯
⚠ TOOLS_CHANGED refund-flow 1 tool change(s)
Watching for changes...
Most eval tools handle single-turn well. EvalView is built for multi-turn — clarification paths, follow-up handling, and tool use across conversations.
name: refund-needs-order-number
turns:
- query: "I want a refund"
expected:
output:
contains: ["order number"]
- query: "Order 4812"
expected:
tools: ["lookup_order", "check_policy"]
forbidden_tools: ["delete_order"]
output:
contains: ["refund", "processed"]
not_contains: ["error"]
thresholds:
min_score: 70Each turn scored independently with conversation context. Per-turn judge scoring, not just final response.
EvalView doesn't just run tests — it understands your agent and configures itself.
Capture real interactions, get pre-configured tests. No YAML writing.
evalview capture --agent http://localhost:8000/invoke
# Use your agent normally, then Ctrl+CAssertion Wizard — analyzing 8 captured interactions
Agent type detected: multi-step
Tools seen search, extract, summarize
Consistent sequence search -> extract -> summarize
Suggested assertions:
1. Lock tool sequence: search -> extract -> summarize (recommended)
2. Require tools: search, extract, summarize (recommended)
3. Max latency: 5000ms (recommended)
4. Minimum quality score: 70 (recommended)
Accept all recommended? [Y/n]: y
Applied 4 assertions to 8 test files
Non-deterministic agents take different valid paths. Let EvalView discover and save them:
evalview check --statistical 10 --auto-variant search-flow mean: 82.3, std: 8.1, flakiness: low_variance
1. search -> extract -> summarize (7/10 runs, avg score: 85.2)
2. search -> summarize (3/10 runs, avg score: 78.1)
Save as golden variant? [Y/n]: y
Saved variant 'auto-v1': search -> summarize
Run N times. Cluster the paths. Save the valid ones. Tests stop being flaky — automatically.
Model got silently updated? Output drifted? --heal retries safe failures, proposes variants for borderline cases, and hard-escalates everything else. It also records when those retries were triggered by a likely model/runtime update.
evalview check --heal ⚠ Model update detected: gpt-5-2025-08-07 → gpt-5.1-2025-11-12 (3 tests affected)
✓ login-flow PASSED
⚡ refund-request HEALED retried — non-deterministic drift
⚡ order-lookup HEALED retried — likely model/runtime update
◈ billing-dispute PROPOSED saved candidate variant auto_heal_a1b2 (score 72)
⚠ search-flow REVIEW tool removed: web_search
✗ safety-check BLOCKED forbidden tool called — cannot heal
3 resolved, 1 candidate variant saved, 1 needs review, 1 blocked.
Model update: 2 of 3 affected tests healed via retry. Run `evalview snapshot` to rebase.
Audit log: .evalview/healing/2026-03-25T14-30-00.json
Decision policy: Retry when tools match but output drifted (non-determinism or likely model/runtime update). Propose a variant when retry fails but score is acceptable. Never auto-resolve structural changes, forbidden tool violations, cost spikes, or score improvements. Full audit trail in .evalview/healing/.
Exit code: 0 only when every failure was resolved via retry. Proposed variants, reviews, and blocks always exit 1 — CI stays honest.
Budget circuit breaker + Smart eval profiles
Budget circuit breaker — enforced mid-execution, not post-hoc:
evalview check --budget 0.50 $0.12 (24%) — search-flow
$0.09 (18%) — refund-flow
$0.31 (62%) — billing-dispute
Budget circuit breaker tripped: $0.52 spent of $0.50 limit
2 test(s) skipped to stay within budget
Smart eval profiles — evalview init detects your agent type and pre-configures evaluators:
Five profiles — chat, tool-use, multi-step, rag, coding — each with tailored thresholds, recommended checks, and actionable tips. Override with --profile rag.
Works with LangGraph, CrewAI, OpenAI, Claude, Mistral, HuggingFace, Ollama, MCP, and any HTTP API.
| Agent | E2E Testing | Trace Capture |
|---|---|---|
| LangGraph | ✅ | ✅ |
| CrewAI | ✅ | ✅ |
| OpenAI Assistants | ✅ | ✅ |
| Claude Code | ✅ | ✅ |
| OpenClaw | ✅ | ✅ |
| Ollama | ✅ | ✅ |
| Any HTTP API | ✅ | ✅ |
Framework details → | Flagship starter → | Starter examples →
┌────────────┐ ┌──────────┐ ┌──────────────┐
│ Test Cases │ ──→ │ EvalView │ ──→ │ Your Agent │
│ (YAML) │ │ │ ←── │ local / cloud │
└────────────┘ └──────────┘ └──────────────┘
evalview init— detects your running agent, creates a starter test suiteevalview snapshot— runs tests, saves traces as baselinesevalview check— replays tests, diffs against baselines, opens HTML reportevalview watch— re-runs checks on every file saveevalview monitor— continuous checks in production with Slack alerts
Snapshot management
evalview snapshot list # See all saved baselines
evalview snapshot show "my-test" # Inspect a baseline
evalview snapshot delete "my-test" # Remove a baseline
evalview snapshot --preview # See what would change without saving
evalview snapshot --reset # Clear all and start fresh
evalview replay # List tests, or: evalview replay "my-test"Your data stays local by default. Nothing leaves your machine unless you opt in to cloud sync via evalview login.
evalview monitor # Check every 5 min
evalview monitor --dashboard # Live terminal dashboard
evalview monitor --slack-webhook https://hooks.slack.com/services/...
evalview monitor --history monitor.jsonl # JSONL for dashboardsNew regressions trigger Slack alerts. Recoveries send all-clear. No spam on persistent failures.
| Feature | Description | Docs |
|---|---|---|
| Assertion wizard | Analyze captured traffic, suggest smart assertions automatically | Above |
| Auto-variant discovery | Run N times, cluster paths, save valid variants | Above |
| Auto-heal | Retry flakes, propose variants, escalate structural changes | Above |
| Budget circuit breaker | Mid-execution budget enforcement with per-test cost breakdown | Above |
| Smart eval profiles | Auto-detect agent type, pre-configure evaluators | Above |
| Baseline diffing | Tool call + parameter + output regression detection | Docs |
| Multi-turn testing | Per-turn tool, forbidden_tools, and output checks | Docs |
| Multi-reference baselines | Up to 5 variants for non-deterministic agents | Docs |
forbidden_tools |
Safety contracts — hard-fail on any violation | Docs |
| Watch mode | evalview watch — re-run checks on file save, with dashboard |
Docs |
| Python API | gate() / gate_async() — programmatic regression checks |
Docs |
| PR comments + alerts | Cost/latency spikes, model changes, collapsible diffs | Docs |
| Terminal dashboard | Scorecard, sparkline trends, confidence scoring | — |
All features
| Feature | Description | Docs |
|---|---|---|
| Multi-turn capture | capture --multi-turn records conversations as tests |
Docs |
| Semantic similarity | Embedding-based output comparison | Docs |
| Production monitoring | evalview monitor --dashboard with Slack alerts and JSONL history |
Docs |
| A/B comparison | evalview compare --v1 <url> --v2 <url> |
Docs |
| Test generation | evalview generate — discovers your agent's domain, generates relevant tests |
Docs |
| Per-turn judge scoring | Multi-turn output quality scored per turn with conversation context | Docs |
| Silent model detection | Alerts when LLM provider updates the model version | Docs |
| Gradual drift detection | Trend analysis across check history | Docs |
| Statistical mode (pass@k) | Run N times, require a pass rate, auto-discover variants | Docs |
| HTML trace replay | Auto-opens after check with full trace details | Docs |
| Verified cost tracking | Per-test cost breakdown with model pricing rates | Docs |
| Judge model picker | Choose GPT, Claude, Gemini, DeepSeek, or Ollama (free) | Docs |
| Pytest plugin | evalview_check fixture for standard pytest |
Docs |
| GitHub Actions job summary | Results visible in Actions UI, not just PR comments | Docs |
| Git hooks | Pre-push regression blocking, zero CI config | Docs |
| LLM judge caching | ~80% cost reduction in statistical mode | Docs |
| Quick mode | gate(quick=True) — no judge, $0, sub-second |
Docs |
| OpenClaw integration | Regression gate skill + gate_or_revert() helpers |
Docs |
| Snapshot preview | evalview snapshot --preview — dry-run before saving |
— |
| Skills testing | E2E testing for Claude Code, Codex, OpenClaw | Docs |
Use EvalView as a library — no CLI, no subprocess, no output parsing.
from evalview import gate, DiffStatus
result = gate(test_dir="tests/")
result.passed # bool — True if no regressions
result.status # DiffStatus.PASSED / REGRESSION / TOOLS_CHANGED
result.summary # .total, .unchanged, .regressions, .tools_changed
result.diffs # List[TestDiff] — per-test scores and tool diffsQuick mode, async, and autonomous loops
Quick mode — skip the LLM judge for free, sub-second checks:
result = gate(test_dir="tests/", quick=True) # deterministic only, $0Async — for agent frameworks already in an event loop:
result = await gate_async(test_dir="tests/")Autonomous loops — gate + auto-revert on regression:
from evalview.openclaw import gate_or_revert
make_code_change()
if not gate_or_revert("tests/", quick=True):
# Change was reverted — try a different approach
try_alternative()Use EvalView as a regression gate in autonomous agent loops.
evalview openclaw install # Install gate skill into workspace
evalview openclaw check --path tests/ # Check and auto-revert on regressionPython API for autonomous loops
from evalview.openclaw import gate_or_revert
make_code_change()
if not gate_or_revert("tests/", quick=True):
try_alternative() # Change was reverteddef test_weather_regression(evalview_check):
diff = evalview_check("weather-lookup")
assert diff.overall_severity.value != "regression", diff.summary()pip install evalview # Plugin registers automatically
pytest # Runs alongside your existing testsclaude mcp add --transport stdio evalview -- evalview mcp serve8 tools: create_test, run_snapshot, run_check, list_tests, validate_skill, generate_skill_tests, run_skill_test, generate_visual_report
MCP setup details
# 1. Install
pip install evalview
# 2. Connect to Claude Code
claude mcp add --transport stdio evalview -- evalview mcp serve
# 3. Make Claude Code proactive
cp CLAUDE.md.example CLAUDE.mdThen just ask Claude: "did my refactor break anything?" and it runs run_check inline.
Works with your coding agent out of the box. Ask Cursor, Claude Code, or Copilot to add regression tests, build a new adapter, or debug a failing check — EvalView ships the architecture maps and task recipes they need to get it right on the first try.
- AGENT_INSTRUCTIONS.md — architecture map, contracts, invariants, verification commands
- Agent Recipes — task-specific playbooks for common extensions
- Add an Adapter
- Add an Evaluator
- Debug Check vs Snapshot Mismatch
- Extend the HTML Report
- Integrate Ollama
| Getting Started | Core Features | Integrations |
|---|---|---|
| Getting Started | Golden Traces | CI/CD |
| CLI Reference | Evaluation Metrics | MCP Contracts |
| Agent Instructions | Agent Recipes | Ollama Recipe |
| FAQ | Test Generation | Skills Testing |
| YAML Schema | Statistical Mode | Chat Mode |
| Framework Support | Behavior Coverage | Debugging |
- Bug or feature request? Run
evalview feedbackor open an issue - Questions? GitHub Discussions
- Setup help? Email hidai@evalview.com
- Contributing? See CONTRIBUTING.md
License: Apache 2.0