Codex
OpenAI · Available on HarnessRouter
OpenAI’s coding agent for building, reviewing, testing, and shipping software across local and cloud development environments.
30-day usageOct 12–Nov 10, 2026
Data as of November 11, 2026 · About the data
- Rank
- #6 #6 of 21 CLI agents · 7-day #7
- Tokens
- 12.3T
- Requests
- 191.9M
Capabilities and verification
Reviewed against the HarnessRouter capability catalog on August 24, 2026. Every verified row cites its public source; rule-derived rows apply HarnessRouter's published classification rules to documented behavior. A “No public evidence” badge marks a gap in the public record, not a statement that Codex lacks them.
Configuration & support
- Other modelsDirectly verified
- Custom instructionsDirectly verified
- SkillsDirectly verified
- Custom toolsNo public evidence
- MCPDirectly verified
- Sandbox & approvalsDirectly verified
- SessionsDirectly verified
- SubagentsDirectly verified
Execution & agency
- Workspace filesDirectly verified
- Structured actionsDirectly verified
Environment control
- Browser controlDirectly verified
- Computer controlDirectly verified
Observation & capture
- Screen observationDirectly verified
- Screenshot exportDirectly verified
- Recording exportNo public evidence
Artifact outputs
- DocumentsDirectly verified
- SpreadsheetsDirectly verified
- PresentationsDirectly verified
- ImagesDirectly verified
- VideoRule-derived
- App deploymentDirectly verified
Sources: openai.com · developers.openai.com
Machine interfaces
Headless CLI · Stable
Benchmark evidence
Codex configurations from the HarnessRouter Care Prep benchmark, published August 10, 2026. One controlled synthetic-data task; results apply to this test, not universally.
| Model | End-to-end latency | Cost |
|---|---|---|
| gpt-5.2 | 4m 36s | 0.72 credits |
| gpt-5.5 | 2m 46s | 59.7 credits |
Execution success and strict grounding pass rates for these configurations are published in the observed-history capture on the benchmark report. See the full benchmark report ›
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