EmberLM

Test, evaluate, and ship AI
that actually works

The developer workspace for LLM testing, model comparison, and prompt evaluation.

app.emberlm.dev/workspace/prompt-lab
prompt-lab / summarize-v3
v3.287% confidence

Summarize the following document in 3 bullet points. Focus on actionable insights. Keep each point under 20 words.

Claude 3.5 Sonnet
1.2s$0.003

- Revenue grew 23% YoY driven by enterprise expansion
- Customer churn dropped to 1.2% after onboarding redesign
- Engineering team should prioritize API v3 migration

All eval rules passed
GPT-4o
1.8s$0.005

- Company saw significant revenue growth this year
- Churn reduction indicates improved user satisfaction
- Technical debt remains a concern for the team

!Failed: specificity check

No SDK required. No setup. Just sign in and start testing.

Everything you need to ship AI with confidence

From first prompt to production. One workspace.

Side-by-side comparison

Run the same prompt across Claude, GPT-4, Gemini, and Llama. See speed, cost, and quality in one view.

Claude 3.5Pass

Revenue grew 23% YoY driven by enterprise expansion...

1.2s$0.003
GPT-4oFail

Company saw significant revenue growth this year...

1.8s$0.005

Prompt versioning

Full version history with diffs. Branch, tag, and rollback prompts like code.

v2.1 -> v2.2+2 -1

- Summarize the document in bullet points.

+ Summarize in exactly 3 bullet points.

+ Keep each under 20 words.

Evaluation engine

LLM-as-a-Judge scoring, custom eval rules, regex checks, JSON schema validation.

Accuracy92%
Relevance88%
Conciseness76%
Formatting95%

MCP server debugger

Paste a server URL, auto-discover tools, test with sample inputs, see the full JSON-RPC trace.

{"method": "tools/call",

"name": "search_docs",

"args": {"query": "auth setup"}

}

200 OK142ms

"Found 3 results..."

Regression testing

Save golden responses. Run tests on every prompt change. Know instantly if quality dropped.

v1
v2
v3
X
v4
v5
v6
v7
v8

Cost analytics

Track spending across all providers. See cost per prompt, per feature, per model.

$48
Claude
$72
GPT-4o
$24
Gemini
$12
Llama

Batch testing

Upload a CSV with 100+ test inputs. Run across models. See pass/fail rates at scale.

user_signup.csv100% pass
checkout_flow.csv94% pass
search_api.csv100% pass

GitHub CI/CD

Connect your repo. Run prompt tests on every PR. Block merges if quality drops. Prompts become first-class code.

feat/new-summary-prompt
All checks passed12/12
fix/tone-adjustment
Blocked9/12
refactor/system-prompt
All checks passed12/12

Confidence score

Every prompt gets a score based on regression results, hallucination risk, and cross-model stability.

Red teaming

One-click security scan. Run jailbreak and injection attacks against your prompt. Find leaks before attackers do.

Fix it for me

One click to get AI-powered prompt improvements. Shorter prompts, better structure, lower cost.

Shareable links

Share any prompt, comparison, or test result with a public link.

Environments

Switch between dev, staging, and prod. All variables change automatically.

Prompt chaining

Build multi-step workflows. Test entire agent pipelines end to end.

Fork collections

Fork a public collection, customize it, make it yours. Share for others to build on.

From idea to production in minutes

01

Write and test your prompt

Open the playground, pick a model, and start testing. Compare outputs across models in real-time. No setup, no SDK, no API keys to manage.

emberlm test --prompt "summarize.md" --models claude,gpt4,gemini
02

Evaluate and lock in quality

Define what a good response looks like. Set up eval rules, build a golden dataset, run regression tests. Get a confidence score before you ship.

emberlm eval --suite golden-set --threshold 95%
03

Ship and monitor

Connect to GitHub for CI/CD. Run tests on every PR. Pipe production traffic back for continuous evaluation. Sleep well.

emberlm ci --on-pr --block-below 90% --notify slack
Developer favorite

The MCP debugger you have been waiting for

Every developer building with MCP servers knows the pain. Cryptic JSON-RPC errors. No visibility into tool discovery. Hours spent debugging what should take minutes. Paste your server URL and get instant visibility into every tool, every parameter, every request and response.

  • -Auto-discover all tools from any MCP server
  • -Visual schema browser with parameter types
  • -Test any tool with sample inputs
  • -Full request/response trace like a network inspector
  • -Record and replay failed agent sessions
  • -Auto-generate mock servers from schema
MCP InspectorConnected

Discovered Tools (6)

search_docs
create_ticket
get_user
update_status
send_email
query_db

Request

{"method": "tools/call",

"params": {"name": "search_docs",

"arguments": {"query": "auth setup"}}}

Response

142ms

{"content": [{"type": "text",

"text": "Found 3 results for auth setup..."}]}

Simple, transparent pricing

Start free. Scale when you are ready.

Free

$0/mo

For individual developers getting started

Get started free
  • 50 LLM calls/month
  • 3 prompt collections
  • 1 MCP server
  • Side-by-side comparison (2 models)
  • 2 environments
  • 5 saved prompt versions
  • Fork public collections
  • Export to code
  • Community support
Most popular

Pro

$49/mo

For developers shipping AI to production

Get Pro
  • 2,000 LLM calls/month
  • Unlimited collections + MCP servers
  • Side-by-side comparison (6 models)
  • Full eval engine + LLM-as-a-Judge
  • Regression testing + golden datasets
  • Batch testing (CSV upload)
  • Confidence scoring
  • "Fix it for me" optimizer
  • Cost analytics
  • Red teaming scans
  • Prompt chaining
  • Auto-generated docs
  • Shareable links
  • Scheduled test runs
  • Unlimited environments
  • Priority support

Team

$149/mo per seat

For teams building AI products together

Get Team
  • 10,000 LLM calls/seat/month
  • Everything in Pro
  • Shared workspaces
  • Prompt review workflows
  • Role-based access control
  • GitHub CI/CD integration
  • Prompt SDK
  • Shadow mode
  • Comments on outputs
  • Natural language test suites
  • Audit log
  • SSO (Google, GitHub, SAML)
  • Dedicated support

Need unlimited calls, custom model hosting, or SLA guarantees? Talk to us.

Frequently asked questions

Stop guessing. Start shipping.

Join developers who test their AI before their users do.

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