AI agents have no sense of time and are not aware of it
Popular coding assistants (Claude Code and Codex) consistently overestimate task duration, guessing ~90 minutes regardless of actual difficulty Self-assessment is severely flawed: models rated their own work ~20 percentage points higher than actual performance, even on failed tasks Runtime behavior depends heavily on the surrounding software harness, not just the underlying model Agents cannot reliably track elapsed time, making long-running autonomous tasks difficult to control Providing explic
Analysis
TL;DR
- Popular coding assistants (Claude Code and Codex) consistently overestimate task duration, guessing ~90 minutes regardless of actual difficulty
- Self-assessment is severely flawed: models rated their own work ~20 percentage points higher than actual performance, even on failed tasks
- Runtime behavior depends heavily on the surrounding software harness, not just the underlying model
- Agents cannot reliably track elapsed time, making long-running autonomous tasks difficult to control
- Providing explicit time-tracking tools dramatically improves temporal accuracy
Why It Matters
This research reveals a critical gap in AI agent reliability for production use: without accurate time estimation and self-assessment, autonomous coding agents cannot be trusted on multi-hour workflows. For practitioners building or deploying AI agents, these findings highlight that model capability alone is insufficient—system design and tooling are equally decisive factors in agent performance.
Technical Details
- Study tested Anthropic's Claude Code and OpenAI's Codex on 200 ProgramBench tasks plus 18 custom benchmarks, measuring both forward time estimates and retrospective elapsed-time reporting
- Both models clustered around a 90-minute estimate regardless of task difficulty; retrospective errors ranged from 3x (Claude) to 6-10x (Codex) actual runtime
- Claude Code ran for a median of ~90 minutes per task, while Codex stopped after ~30 minutes, despite using similar underlying models—demonstrating harness-driven behavioral divergence
- Older models (Opus 4.8, GPT-5.5) overrated their results by ~20 points on average, claiming ~70% success on tasks that actually scored 7-14.5%
- When given access to an explicit elapsed-time tool, agents achieved near-perfect temporal accuracy, suggesting the limitation is architectural rather than inherent to the models
Industry Insight
- Agent harness design is as critical as model selection—identical models can produce drastically different outcomes depending on software wrappers, making benchmarking must include runtime behavior, not just capability
- Self-assessment calibration should be a standard evaluation metric for any agent deployment targeting long-running or autonomous workflows
- The fix is straightforward: integrating real-time tooling (clocks, timers) into agent loops can resolve temporal blind spots, suggesting that robust agent frameworks should bake in observability by default rather than relying on model intuition
Disclaimer: The above content is generated by AI and is for reference only.