On our first full real-world evaluation run, Cursor CLI (Composer-1) ranks #1 on Sigmabench, leading the field in overall score and showing standout performance across complex software engineering tasks.

What we measured:

• Sigmascore — the overall measure of an agent’s real-world coding performance
• Accuracy — how often outputs meet quality thresholds
• Consistency — how often outputs remain useful even when not fully completing a task
• Speed — how quickly tasks are completed

Each score is assigned a tier based on how close they are with respect to the margin of error. The top-scoring group of agents are in Tier 1, the next-best group are in Tier 2, and so on.

Cursor (Composer-1) is the overall leader on the Sigmabench benchmark:

• It’s the only Tier 1 agent on Sigmascore
• It’s the only Tier 1 agent on Speed
• It’s Tier 2 on both Accuracy and Consistency

Comparisons

Cursor (Composer-1) vs Codex CLI (GPT-5.1 Codex Max)

Codex is both the most accurate (+5.2 points) agent in this comparison. Consistency is statistically tied. Cursor, however, leads by a large margin of 27 percentage points in speed, representing about a 4x speed advantage.

Cursor CLI (Composer-1) vs Claude Code (Opus 4.5)

Claude Code (Opus 4.5) and Cursor CLI are statistically tied on Consistency. Claude Code is leading by a full tier in Accuracy. Cursor leads once again by a large margin of 27 percentage points in speed, representing about a 4x speed advantage.

Key Insights

• Speed advantage: Cursor CLI (Composer-1) is 4x faster on average than both Claude Code (Opus 4.5) and Codex CLI (GPT-5.1-Codex-Max).

• Cursor CLI (Composer-1) trails the accuracy leader Codex CLI (GPT-5.1-Codex-Max) by 5 percentage points, and is tied on Consistency. The speed advantage is significant enough to maintain the #1 Sigmascore rank overall. points, but the speed advantage is significant enough to maintain the #1 Sigmascore rank overall.