Intelligent Cross-Tool AI Routing

Tessera doesn't just use one AI tool — it routes each code generation task to the best tool and model for the job. This multi-AI approach produces better results than any single tool alone.

How It Works

Complexity	Default	Fallback chain
Simple	Claude Haiku	Gemini Flash → Codex
Medium	Claude Sonnet	Gemini Pro → Claude Haiku → Gemini Flash
Complex	Claude Opus	Gemini Pro → Claude Sonnet → Gemini Flash

A single project build might use Claude Opus for database architecture, Gemini Flash for SETUP.md, and Claude Sonnet for tests — each task routed to the best model automatically.

Plan-Aware Routing

During setup, Tessera asks about your AI subscription plans to optimize routing and cost:

What AI plans do you have?
  Claude plan: [Max (unlimited) / Pro / Free]
  Codex plan:  [Plus (ChatGPT Plus) / Free]
  Gemini plan: [Pro (Google One AI Premium) / Free]

Plan tier	Examples	Routing behavior
Unlimited	Claude Max	Preferred for everything
Generous	Claude Pro, Codex Plus	Preferred but balanced
Limited	Free tiers	Fallback only

With Claude Max, even simple tasks use Claude (Haiku) — no reason to route elsewhere when it's free.

Rate Limit Handling

If a tool hits rate limits mid-build, Tessera handles it automatically:

1. Detects the error (13 different patterns recognized)
2. Marks the tool with a 2-minute cooldown
3. Switches to the next tool in the fallback chain
4. Shows you what happened: claude rate-limited (cooldown: 120s). Trying next tool...

No manual intervention needed. The build keeps going.

AI Peer Review

After generating the frontend theme and admin panel, a different AI reviews the output for quality assurance:

✓ Designing frontend theme           (claude opus)
⏳ Peer review: frontend theme
  Reviewer: gemini (gemini-2.0-flash)
  Review found 2 issue(s) — applying fixes...
  ✓ Review fixes applied (2 issues)

• Multiple tools available: different tool reviews (Claude generates, Gemini reviews)
• Single tool available: lighter model reviews (Opus generates, Haiku reviews)
• Cost: 1 cheap AI call per reviewed step

This built-in peer review catches issues that a single AI pass would miss — similar to human code review, but instant.

Check Your Routing

Run tessera tools to see which AI tools are installed and how tasks will be routed:

tessera tools

Available AI tools:
✓ claude: 2.1.75
✓ gemini: 0.32.1
✓ codex: 0.98.0

AI routing:
  plans: claude=max (unlimited), codex=plus (generous), gemini=free (limited)
  simple: claude (claude-haiku-4-5-20251001)
  medium: claude (claude-sonnet-4-20250514)
  complex: claude (claude-opus-4-20250514)

This is useful after installing a new AI tool, or to verify your plan configuration is correct.

Usage Summary

At the end of each build, Tessera shows how many calls each tool handled:

AI usage: claude: 5 calls (2 opus, 2 sonnet, 1 haiku) | gemini: 2 calls (2 flash)

Environment Variables

Most users don't need these — the installer asks interactively. For CI/CD or automation:

TESSERA_CLAUDE_PLAN=max       # max | pro | free
TESSERA_CODEX_PLAN=plus       # plus | free
TESSERA_GEMINI_PLAN=free      # pro | free
TESSERA_TOOL_PREFERENCE=gemini,claude,codex  # custom order
TESSERA_TOOL_EXCLUDE=codex    # never use this tool

Related

• Creating a Project — see AI routing in action during a full build
• Resume & Recovery — what happens when a routed task fails