Composer 2.5 vs GPT-5.5

GPT-5.5 is a frontier API model with strong terminal-agent and SWE-Bench Verified rows, while Composer 2.5 is a Cursor-native coding agent priced for IDE workflows. The right choice depends on whether you need a general production model or a cheaper agent inside Cursor.

Pick GPT-5.5 for external APIs, terminal-heavy automation, 1M-token workflows, and verified coding benchmark confidence. Pick Composer 2.5 when you are already in Cursor and want the lower standard token price. Composer's SWE-Bench Multilingual score is not the same benchmark as GPT-5.5's SWE-Bench Verified row.

Decision scorecard

Local evidence first

Signal	Composer 2.5	GPT-5.5	How to read it
Product type	IDE-native agent built on Kimi K2.5	Standalone API model	Read downstream rows through the product-type lens before comparing benchmarks, prices, or provider availability.
Best for	Long Cursor IDE sessions and autonomous in-IDE coding	API builders, multimodal apps, and non-IDE automation	Use-case synthesis from product type, capability flags, context, and provider data.
Decision fit	Coding, RAG, and Agents	Coding, RAG, and Agents	Primary workload tags from local decision data.
Context window	1m	1.05m	Higher is better when prompts, retrieval chunks, or transcripts are large.
Cheapest output	$2.50/1M tokens	$30/1M tokens	Cheapest tracked provider route; verify your exact region and tier.
Provider routes	1 tracked	4 tracked	Broader coverage can reduce vendor lock-in and fallback risk.
Shared benchmarks	2 shared	Terminal-Bench 2.0 leader	Visible benchmark lead is 13.4 points on Terminal-Bench 2.0.

Decision tradeoffs

Choose Composer 2.5 when...

Composer 2.5 has the lower cheapest tracked output price at $2.50/1M tokens.
Composer 2.5 uniquely exposes IDE integration and Parallel agents in local model data.
Local decision data tags Composer 2.5 for Coding, RAG, and Agents.

Choose GPT-5.5 when...

GPT-5.5 holds a shared-benchmark lead on Terminal-Bench 2.0, ahead by 13.4 points.
GPT-5.5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
GPT-5.5 has broader tracked provider coverage for fallback and procurement flexibility.
GPT-5.5 uniquely exposes Vision, Multimodal, and Reasoning in local model data.
Local decision data tags GPT-5.5 for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Composer 2.5

Requests / monthInput tokens / requestOutput tokens / request

Composer 2.5

$1,025

Cheapest tracked route/tier: Cursor Standard async

GPT-5.5

$11,500

Cheapest tracked route/tier: OpenAI API 0-272K input tokens

Estimated monthly gap: $10,475. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Composer 2.5 -> GPT-5.5

No overlapping tracked provider route is sourced for Composer 2.5 and GPT-5.5; plan for SDK, billing, or endpoint changes.
GPT-5.5 is $27.50/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
Check replacement coverage for IDE integration and Parallel agents before moving production traffic.
GPT-5.5 adds Vision, Multimodal, and Reasoning in local capability data.

GPT-5.5 -> Composer 2.5

No overlapping tracked provider route is sourced for GPT-5.5 and Composer 2.5; plan for SDK, billing, or endpoint changes.
Composer 2.5 is $27.50/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
Check replacement coverage for Vision, Multimodal, and Reasoning before moving production traffic.
Composer 2.5 adds IDE integration and Parallel agents in local capability data.

Specs

Specification	Composer 2.5 Cursor (Anysphere)	GPT-5.5 OpenAI
Released	2026-05-18	2026-04-23
Context window	1m	1.05m
Parameters	—	—
Architecture	-	Decoder Only
License	Proprietary	Proprietary
Openness	Proprietary	Proprietary
Weights	Not released	Not released
Code	Not released	Unknown
Commercial use	Commercial use: conditional	Commercial use: conditional
Knowledge cutoff	-	2025-12

Pricing and availability

Pricing attribute	Composer 2.5	GPT-5.5
Input price	Standard async $0.50/1M tokens Cursor Composer 2.5 standard tier. Fast interactive $3/1M tokens Cursor says fast has the same intelligence and is the default.	0-272K input tokens $5/1M tokens Standard GPT-5.5 token pricing before the long-context surcharge threshold. 272K+ input tokens $8/1M tokens Long-context surcharge applies above 272K input tokens for the full session.
Output price	Standard async $2.50/1M tokens Cursor Composer 2.5 standard tier. Fast interactive $15/1M tokens Cursor says fast has the same intelligence and is the default.	0-272K input tokens $30/1M tokens Standard GPT-5.5 token pricing before the long-context surcharge threshold. 272K+ input tokens $36/1M tokens Long-context surcharge applies above 272K input tokens for the full session.
Providers	Cursor	OpenAI API OpenRouter Vercel AI Gateway AWS Bedrock

Capabilities

Capability	Composer 2.5	GPT-5.5
Vision	No	Yes
Multimodal	No	Yes
Reasoning	No	Yes
Function calling	Yes	Yes
Tool use	Yes	Yes
Structured outputs	No	Yes
Code execution	Yes	Yes
IDE integration	Yes	No
Computer use	No	No
Parallel agents	Yes	No

Benchmarks

Benchmark	Composer 2.5	GPT-5.5
Terminal-Bench 2.0	69.3	82.7
CursorBench	63.2	64.3

Harness caveat. Composer 2.5 is measured as IDE-native agent built on Kimi K2.5, while GPT-5.5 is standalone API model. Treat shared benchmark scores as directional because IDE or product scaffolding, tool access, prompt routing, and interaction mode can change real application results.

Deep dive

GPT-5.5 has the stronger sourced terminal-agent signal in this pair: 82.7% on Terminal-Bench 2.0 versus Composer 2.5 at 69.3% on the same benchmark version. If the workload is shell-heavy debugging, command execution, CI repair, or tool orchestration outside an IDE, GPT-5.5 is the safer first test.

The SWE-Bench caveat remains necessary. GPT-5.5 has a sourced SWE-Bench Verified row at 88.7%. Composer 2.5 does not have a published Verified score in the seed; its 79.8% row is SWE-Bench Multilingual from Cursor's agent context. That row is useful for Cursor workflow fit, not as a direct GPT-5.5 leaderboard comparison.

Composer's cost advantage is large at the standard tier. It lists $0.50/M input and $2.50/M output, while GPT-5.5 standard rows list $5/M input and $30/M output. For Cursor-only coding where the model does not need to leave the IDE, that price gap can outweigh GPT-5.5's broader benchmark and API strengths.

GPT-5.5 is the production integration pick because it is a model route rather than a bundled IDE agent. It carries tracked OpenAI, OpenRouter, and Vercel routes, plus a 1M-class context row and multimodal support in the seed data. Composer should be evaluated as a Cursor product decision.

FAQ

Which is better for terminal automation?

GPT-5.5 has the stronger sourced terminal signal: 82.7% on Terminal-Bench 2.0 versus Composer 2.5 at 69.3% on the same benchmark version. Start with GPT-5.5 for shell-heavy or CI automation outside Cursor.

Is Composer 2.5 cheaper than GPT-5.5?

Yes at standard pricing. Composer 2.5 lists $0.50/M input and $2.50/M output, while GPT-5.5 lists $5/M input and $30/M output. Composer's lower price is tied to Cursor's product surface rather than a standalone API route.

Can I compare Composer's 79.8% to GPT-5.5's 88.7%?

No. Composer's 79.8% is SWE-Bench Multilingual; GPT-5.5's 88.7% is SWE-Bench Verified. They are different benchmark rows, so the page should use them as separate signals rather than one ranked scale.

Which model should a product team integrate?

GPT-5.5 is the better integration candidate because it has tracked API/provider routes and a general model surface. Composer 2.5 is a Cursor-native agent, so it is better treated as an IDE workflow choice.

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Model pages

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Last reviewed: 2026-06-30. Data sourced from public model cards and provider documentation.

Both models

Composer 2.5 GPT-5.5