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BenchLM
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GPT-5.2-Codex vs Muse Spark 1.2

Updated November 4, 2026. Rank says Muse Spark 1.2 is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.

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Decision reading

Muse Spark 1.2 has the higher public point estimate, 65.41 versus 56.25. Their conditional score ranges overlap. These ranges do not establish rank confidence. 1 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.

Model A
OpenAI logo

OpenAI

56.25/100

Estimated · Public rank #60

Conditional range 46.5–66.0

Model B
Meta logo

Meta

65.41/100

Supported · Public rank #28

90% interval 59.0–71.8

Shared results
1
GPT-5.2-Codex only
4
Muse Spark 1.2 only
8
Like-for-like categories
1 / 8
Estimated: GPT-5.2-Codex · Supported: Muse Spark 1.2. Conditional ranges do not establish rank confidence.How the comparison works

Which one for your work

Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.

  • Coding work

    Code generation, repair, and software-engineering tasks

    Muse Spark 1.2

    Muse Spark 1.2 has the higher public coding point estimate, 52.8 to 44.5, with Supported evidence for both models. The conditional ranges do not establish rank confidence.

    Confidence: limited
  • Long documents

    Prompts that approach the documented context limit

    Muse Spark 1.2

    Muse Spark 1.2 has the larger documented context window.

    Confidence: documented
  • Chat turn cost

    1K fresh input + 500 output tokens

    Muse Spark 1.2

    Muse Spark 1.2 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates
Show secondary and unsupported calls
  • Cache-heavy agent loop cost

    200K cached + 20K fresh input + 10K output tokens

    Muse Spark 1.2

    Muse Spark 1.2 has the lower estimated token cost for this stated workload. GPT-5.2-Codex has no published cached-input rate, so cached tokens use its listed input rate.

    Confidence: rate-fallback
  • Repository review cost

    50K fresh input + 3K output tokens

    Muse Spark 1.2

    Muse Spark 1.2 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.

    Confidence: listed-rates
  • Agentic work

    Tool use, computer use, and multi-step task completion

    Not enough matched evidence

    GPT-5.2-Codex is scored on Estimated evidence for agentic, so the reading is directional rather than like-for-like.

    Confidence: limited

Which one for a specific job

Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.

The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.

44.5GPT-5.2-Codex52.8Muse Spark 1.2

Like-for-like · BenchAlign v5.8

Muse Spark 1.2 has the higher coding point estimate. Conditional score ranges do not establish rank confidence.

Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.

Same basis rules as the category table below

What is actually comparable

Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.

2 categories rest on Estimated evidence or different evidence sets. Those rows remain visible for coverage context but do not name a winner.

Shape of the matched evidence

Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.

A shared-evidence shape is not available.

BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.

Category results, on a stated basis

Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.

Coding

Like-for-like
GPT-5.2-Codex
44.5
Supported · #59/156
Muse Spark 1.2
52.8
Supported · #37/156
Basis
BenchAlign v5.8 lane · 3 vs 5 public rows
Reading
Muse Spark 1.2 leads · intervals overlap

Agentic

Directional only
GPT-5.2-Codex
44.7
Estimated · #66/135
Muse Spark 1.2
59.9
Supported · #31/135
Basis
BenchAlign v5.8 lane · 2 vs 3 public rows
Reading
Directional only

Knowledge

Directional only
GPT-5.2-Codex
56.9
Estimated · #55/179
Muse Spark 1.2
64.7
Supported · #33/179
Basis
BenchAlign v5.8 lane · 0 vs 1 public rows
Reading
Directional only

Reasoning

Not comparable
GPT-5.2-Codex
81.5
Unranked · 2 rankable rows
Muse Spark 1.2
79.3
Unranked · 2 rankable rows
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multimodal

Not comparable
GPT-5.2-Codex
77.2
Unranked · 1 rankable row
Muse Spark 1.2
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Multilingual

Not comparable
GPT-5.2-Codex
Not ranked
Muse Spark 1.2
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Instruction following

Not comparable
GPT-5.2-Codex
93.8
#5/157
Muse Spark 1.2
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Math

Not comparable
GPT-5.2-Codex
Not ranked
Muse Spark 1.2
Not ranked
Basis
Provisional lane · 0 vs 0 weighted rows
Reading
Not comparable

Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.

Supported evidence per lane · bars run 0–100Methodology

What each workload costs

Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.

Chat turn

1K fresh input + 500 output tokens

GPT-5.2-Codex
$0.00875
Fits in one request
Muse Spark 1.2
$0.00338
Fits in one request

Muse Spark 1.2 has the lower modeled cost

Costs use the listed standard API rates.

Repository review

50K fresh input + 3K output tokens

GPT-5.2-Codex
$0.1295
Fits in one request
Muse Spark 1.2
$0.07525
Fits in one request

Muse Spark 1.2 has the lower modeled cost

Costs use the listed standard API rates.

Cache-heavy agent loop

200K cached + 20K fresh input + 10K output tokens

GPT-5.2-Codex
$0.525
Fits in one request
Cached input priced at the published list-input rate
Muse Spark 1.2
$0.0975
Fits in one request

Muse Spark 1.2 has the lower modeled cost

GPT-5.2-Codex has no published cached-input rate, so cached tokens use its listed input rate.

Cached input falls back to the list input rate only where a cached rate is unpublished

Specification differences

Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.

Cached-input rate

A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.

GPT-5.2-Codex

Not published

Muse Spark 1.2

$0.15 per 1M cached input tokens

Meta: Muse Spark 1.2 model page

Documented inputs

GPT-5.2-Codex

Not sourced

Muse Spark 1.2

Not sourced

Documented outputs

GPT-5.2-Codex

Not sourced

Muse Spark 1.2

Not sourced

Provider availability

GPT-5.2-Codex

Not sourced

Muse Spark 1.2

Not sourced

Reasoning profile

GPT-5.2-Codex

Reasoning

Muse Spark 1.2

Reasoning

Weight access

GPT-5.2-Codex

Proprietary

Muse Spark 1.2

Proprietary

License

GPT-5.2-Codex

Proprietary

Muse Spark 1.2

Proprietary

Release date

GPT-5.2-Codex

2025-12-18

Muse Spark 1.2

2026-08-05

If you already use one of these models

Deployment change
The models list different providers, so authentication, endpoint behavior, limits, and feature support may change.
Quality signal
Muse Spark 1.2 has the higher public point estimate, 65.41 versus 56.25. Their conditional score ranges overlap. These ranges do not establish rank confidence.
Workload cost
Repository review: $0.1295 vs $0.07525. Cache-heavy agent loop: $0.525 vs $0.0975.
Context tradeoff
Muse Spark 1.2 has the larger documented window (1M).
Run the same representative tasks against both endpoints before changing production traffic.

Questions

Which is better, GPT-5.2-Codex or Muse Spark 1.2?

Muse Spark 1.2 has the higher public point estimate, 65.41 versus 56.25. Their conditional score ranges overlap. These ranges do not establish rank confidence. The page therefore keeps the decision tied to the specific documented workload.

Which is better for coding, GPT-5.2-Codex or Muse Spark 1.2?

Muse Spark 1.2 has the higher public coding point estimate, 52.8 to 44.5, with Supported evidence for both models. The conditional ranges do not establish rank confidence.

Which is better for agentic tasks, GPT-5.2-Codex or Muse Spark 1.2?

Muse Spark 1.2 scores higher for agentic tasks on the public lane, 59.9 to 44.7. GPT-5.2-Codex is scored on Estimated evidence for agentic tasks, so the reading is directional rather than like-for-like. BenchLM does not name a winner for agentic tasks from a directional reading; read the shared benchmark rows directly and test the models on the same task set.

Which costs less, GPT-5.2-Codex or Muse Spark 1.2?

For the stated presets, chat costs $0.00875 on GPT-5.2-Codex and $0.00337 on Muse Spark 1.2; repository review costs $0.1295 and $0.07525; the cache-heavy agent loop costs $0.525 and $0.0975. GPT-5.2-Codex has no published cached-input rate, so cached tokens use its listed input rate.

Which has the larger context window, GPT-5.2-Codex or Muse Spark 1.2?

Muse Spark 1.2 has the larger documented context window: 1M, compared with 400K.

Benchmark evidence

The full public result ledger is available for audit without forcing a wide desktop table onto a phone.

Browse raw public benchmark evidence13 rows

Agentic

  • Gert Labs

    GPT-5.2-Codex51.79%
    Source
    Muse Spark 1.2—

    Not directly comparable

  • JobBench

    GPT-5.2-Codex26.0%
    Source
    Muse Spark 1.2—

    Not directly comparable

  • Terminal-Bench 2.1

    GPT-5.2-Codex—
    Muse Spark 1.282.9%
    Source

    Not directly comparable

  • Terminal-Bench 2.1 (Vals)

    GPT-5.2-Codex—
    Muse Spark 1.269.7%
    Source

    Not directly comparable

  • MazeBench

    GPT-5.2-Codex—
    Muse Spark 1.20%
    Source

    Not directly comparable

Coding

  • Vibe Code Bench

    GPT-5.2-Codex37.91%
    Source
    Muse Spark 1.2—

    Not directly comparable

  • LiveCodeBench (Vals)

    GPT-5.2-Codex88.0%
    Source
    Muse Spark 1.2—

    Not directly comparable

  • SWE-bench (Vals)

    GPT-5.2-Codex72.4%
    Source
    Muse Spark 1.286.6%
    Source

    Muse Spark 1.2 leads this result

  • Terminal-Bench 2.1

    GPT-5.2-Codex—
    Muse Spark 1.282.9%
    Source

    Not directly comparable

  • DeepSWE

    GPT-5.2-Codex—
    Muse Spark 1.259.3%
    Source

    Not directly comparable

  • VulcanBench v3

    GPT-5.2-Codex—
    Muse Spark 1.287.0%
    Source

    Not directly comparable

  • FrontierSWE v2

    GPT-5.2-Codex—
    Muse Spark 1.212.0%
    Source

    Not directly comparable

Knowledge

  • MMLU-Pro (Vals)

    GPT-5.2-Codex—
    Muse Spark 1.288.3%
    Source

    Not directly comparable

13 public results · 1 shared

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Last updated November 4, 2026