Bob Lens Visual Change Intelligence
IBM BOB HACKATHON 2026

Bob Lens

See what Bob changed.
Understand it. Approve it.

npm install -g https://github.com/preyashyadav/bob-lens
bob-lens init && bob-lens start
1.7x more bugs in AI code — CodeRabbit 2025
43% of AI changes need production debugging — Lightrun 2026
Amazon: 6.3M lost orders from unreviewed AI code — March 2026

The Gap No Tool Fills

AI writes code at machine speed. Review happens at human speed. Nothing bridges them.

Bob writes code
???
What changed behaviorally? What values flow through? What's the risk?
Developer approves
Production

What exists today

  • PR review tools — post-commit only
  • Static analyzers — no execution context
  • Code diffs — lines changed, not behavior changed

What Bob Lens adds

  • Real-time detection via MCP — before any commit
  • BobShell analysis — Bob explaining its own changes
  • Visual execution flow — see value movement between functions
  • Component preview — see UI changes rendered, not just coded

One Command. Full Visibility.

Step 1 — Install
npm install -g https://github.com/preyashyadav/bob-lens
Global install. Works on any project. No configuration.
Step 2 — Initialize
cd your-project
bob-lens init
Creates .bob/mcp.json, AGENTS.md, bob_sessions/ automatically. Bob IDE connects instantly.
Step 3 — Start
bob-lens start
UI on :3333, WebSocket bridge on :8080, Sandbox on :3334. Open browser. Done.
Step 4 — Connect MCP
Bob IDE → MCP Settings → Restart bob-lens → Enable auto-approve
One-time setup. Auto-reconnects after that.

Bob Makes a Change. Bob Lens Explains It.

app.js BACKEND
BEFORE
1 const getProducts = (req, res) => {
2 res.json({ data: products });
3 };
AFTER
1 const getProducts = (req, res) => {
2 + const discounted = applyDiscount(products);
3 + const taxed = applyTax(discounted);
4 -/+ res.json({ data: taxed });
DIFF
@@ -1,3 +1,5 @@
const getProducts = (req, res) => {
- res.json({ data: products });
+ const discounted = applyDiscount(products);
+ const taxed = applyTax(discounted);
+ res.json({ data: taxed });
};
BEFORE
ROUTE
GET /products
app.js:1
RETURN
return products
app.js:2
AFTER
ROUTE
GET /products
app.js:1 unchanged
FUNCTION
applyDiscount
app.js:8
NEW
number (e.g. 90)
FUNCTION
applyTax
app.js:12
NEW
number (e.g. 97.2)
RETURN
return taxed
app.js:16
MODIFIED
Click a node to inspect input, intent, and output.
BEFORE
Sample Name
user
AFTER
Sample Name
user
Puppeteer renders the actual React component — not a screenshot of code.

Built On IBM Bob. Not Around It.

notify_change · ask_bob · run_test
Bob Lens registers as a native MCP server. Bob calls notify_change automatically after every file change — no webhooks, no polling, no manual trigger.
bob -p 'analyze' --output-format stream-json
Bob Lens spawns BobShell programmatically to analyze changes. The AI that wrote the code explains its own changes. No third-party LLM calls.
git show HEAD:file
Before-state is read from Bob's shadow Git repository. Zero manual state management — Bob's checkpoint system handles it automatically.
Auto-generated. Bob follows it natively.
bob-lens init generates an AGENTS.md that instructs Bob to always invoke notify_change. No custom prompting required at runtime.

Every Change. Documented.

Bob Lens exports a complete JSON session report for every analyzed change. Includes the full execution flow, risk analysis, verdict, and all affected nodes — saved to bob_sessions/ automatically. 

{
  "tool": "Bob Lens",
  "exported_at": "2026-05-17T04:48:14Z",
  "change": {
    "description": "Added applyTax function",
    "verdict": "safe"
  },
  "analysis": {
    "risks": [
      "Tax rate is hardcoded",
      "No input validation"
    ],
    "nodes_added": 2,
    "nodes_modified": 1
  }
}
1.7x
AI code has 1.7x more bugs (CodeRabbit, 2025)
2 commands
Install and start Bob Lens
$30.1B
AI code market by 2032