Your SDRs spend just 35% of their time actually selling. The rest? Research, data entry, writing emails, prepping for calls. Both Claude and ChatGPT promise to automate this busywork—but they take different approaches.
After running both AIs on real sales workflows at MarketBetter (and building an AI SDR with OpenClaw), here's what we learned about when to use each.
Three AI tools. All capable. But which one should your GTM team actually use?
With GPT-5.3-Codex dropping February 5, 2026, the landscape just shifted. Again. This guide breaks down OpenAI Codex, Claude Code, and ChatGPT for sales and marketing use cases—with specific recommendations for each workflow.
| Use Case | Best Tool | Why |
|---|---|---|
| Code generation/scripts | Codex | Purpose-built, best performance |
| Long research/analysis | Claude | 200K context, better reasoning |
| Quick answers/chat | ChatGPT | Fast, good enough for simple tasks |
| Email personalization | Claude | Nuanced writing, follows instructions |
| Pipeline automation | Codex + OpenClaw | Agentic capabilities, mid-turn steering |
| Sales call prep | Claude | Better at synthesis and summary |
| Proposal generation | Claude | Longer document handling |
Now let's dig into the details.
Released: February 5, 2026
What it is: OpenAI's most capable agentic coding model
Building Sales Automation Scripts
Pipeline Monitoring Systems
Custom Sales Tools
What it is: Claude 3.5/4 with tool use and code execution
Integrated into: VS Code, terminal, OpenClaw
Prospect Research
Email Writing
Document Analysis
Sales Coaching
What it is: OpenAI's general-purpose assistant
Best for: Quick tasks, brainstorming, general questions
Quick Research
Brainstorming
Light Automation
| Tool | Context Window | Implication |
|---|---|---|
| Claude | 200K tokens | Can analyze ~500 pages at once |
| ChatGPT | 128K tokens | Good for most tasks |
| Codex | Varies by task | Designed for code, not documents |
Winner for GTM: Claude. When researching prospects or analyzing long conversations, context matters.
Claude excels at following precise instructions. If you say "write exactly 3 bullet points," you get 3 bullet points.
ChatGPT tends to add extra context or caveats.
Codex is excellent for technical instructions but can over-engineer simple requests.
Winner for GTM: Claude for content, Codex for technical tasks.
Codex was built for autonomous work. The mid-turn steering feature lets you redirect it without starting over.
Claude can be agentic via OpenClaw but requires more setup.
ChatGPT's agentic features are limited.
Winner for GTM: Codex for automation, Claude via OpenClaw for custom agents.
| Tool | Response Time | Throughput |
|---|---|---|
| ChatGPT | Fastest | Best for high-volume |
| Claude | Medium | Good for quality |
| Codex | Varies | Designed for complex tasks |
Winner for GTM: Depends on use case. ChatGPT for quick tasks, Codex for batch processing.
Based on our analysis, here's the optimal setup:
| Tool | OpenClaw Support | Setup |
|---|---|---|
| Claude | Native | Add API key |
| GPT-4 | Native | Add API key |
| Codex | Via API | Requires custom config |
OpenClaw works best with Claude due to Anthropic's tool use design.
We tested all three on the same task: Write a personalized cold email for a VP of Sales at a 200-person SaaS company.
Followed the template exactly. Referenced specific company details. Professional but warm tone. 94 words (as requested).
Added extra context we didn't ask for. Good personalization but verbose. 147 words (missed the target).
Technical and formal. Suggested code-like structures. Not ideal for email writing.
Winner: Claude for email personalization.
There's no single best tool. The right answer depends on your workflow:
The smartest teams use multiple tools for different tasks rather than forcing one tool to do everything.
Want AI that's already integrated? MarketBetter combines visitor identification, AI-powered playbooks, and automated outreach in one platform. No prompt engineering required. Book a demo.
