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Comparison · 3 models · Updated Nov 2, 2026

CoBuddy vs Perceptron Mk1 vs Solar Pro 4

Solar Pro 4 comes out ahead, 53 to 46 and 45 on our weighted score, though Perceptron Mk1 is 7% cheaper per token.

  1. Baidu

    CoBuddy

    Released May 6, 2026

    46/100
    • ECI—
    • Price$0.28 / $1.13
    • Context131K
  2. Perceptron

    Perceptron Mk1

    Released May 12, 2026

    45/100
    • ECI—
    • Price$0.15 / $1.50
    • Context33K
  3. Our pick

    Upstage

    Solar Pro 4

    Released Aug 6, 2026

    53/100
    • ECI—
    • Price$0.30 / $1.20
    • Context524K
01 — Verdict

Solar Pro 4 is our pick

Solar Pro 4 is the better all-round choice, scoring 53/100 against CoBuddy (46) and Perceptron Mk1 (45). It leads on context window. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

  • CapabilityNot enough dataNo independent benchmark covers every model here yet
  • Lowest pricePerceptron Mk1Perceptron Mk1 $0.487 · CoBuddy $0.492 · Solar Pro 4 $0.525 per 1M tokens (3:1 blend)
  • Longest contextSolar Pro 4Solar Pro 4 524,288 · CoBuddy 131,072 · Perceptron Mk1 32,768 tokens
  • Widest inputsPerceptron Mk1CoBuddy: Text · Perceptron Mk1: Text, Images, Video · Solar Pro 4: Text
  • Self-hostingNo open weightsAll three are available only through APIs
How the score is built
MeasureWeightCoBuddyPerceptron Mk1Solar Pro 4
Price50%626260
Inputs & features30%354545
Context window20%25049
Overall100%46/10045/10053/100

Left out because at least one model lacks the data: capability. The remaining weights were rescaled.

02 — Side by side

Every spec in one table

Highlighted cells lead their row. Dashes mean the data is not published.

CoBuddy vs Perceptron Mk1 vs Solar Pro 4 specifications side by side
SpecificationCoBuddyBaiduPerceptron Mk1PerceptronSolar Pro 4Upstage
Capability
Capabilities Index (ECI)———
ECI rank———
Price per million tokens
Input$0.28$0.15 (best)$0.30
Output$1.13 (best)$1.50$1.20
Cached input——$0.06
Blended (3:1)$0.492$0.487 (best)$0.525
Long-context rateSame rateSame rateSame rate
Price sourceMedian of 1 providersMedian of 3 providersOfficial Upstage API
Limits
Context window131,072 tokens32,768 tokens524,288 tokens (best)
Max output65,536 tokens8,192 tokens131,072 tokens (best)
Inputs and features
TextYesYesYes
ImagesNoYesNo
PDFsNoNoNo
AudioNoNoNo
VideoNoYesNo
ReasoningYesYesYesminimal · low · medium · high · xhigh · max
Tool callingYesNoYes
Structured outputNoNoYes
Availability
WeightsProprietaryProprietaryProprietary
API model ID——solar-pro4
API providers136 (best)
ReleasedMay 6, 2026May 12, 2026Aug 6, 2026
Knowledge cutoff——Feb 2026
03 — Cost

What would a month cost?

Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.

  • CoBuddy$5.06
  • Perceptron Mk1$4.50
  • Solar Pro 4$5.40
04 — Questions

Which should you choose?

Which is better: CoBuddy, Perceptron Mk1 or Solar Pro 4?

Solar Pro 4 is the better all-round choice, scoring 53/100 against CoBuddy (46) and Perceptron Mk1 (45). It leads on context window. The score weighs price 50%, inputs & features 30%, context window 20%. None of the shared benchmarks cover every model here yet, so capability is left out of this verdict.

Which is cheaper, CoBuddy, Perceptron Mk1 or Solar Pro 4?

Perceptron Mk1 is cheaper at $0.15 input / $1.50 output per million tokens (median across 3 API providers). CoBuddy costs $0.28 input / $1.13 output per million tokens (median across 1 API provider); Solar Pro 4 costs $0.30 input / $1.20 output per million tokens (official Upstage API price). At a typical mix of three input tokens to one output token, that is $0.487 per million tokens for Perceptron Mk1 versus $0.492 for CoBuddy (1× as much) and $0.525 for Solar Pro 4 (1.1× as much).

Which scores higher on benchmarks?

There is no independent benchmark that covers all three models yet. CoBuddy has not been scored yet, Perceptron Mk1 has not been scored yet and Solar Pro 4 has not been scored yet.

Which is better for coding?

There are no published SWE-bench Verified results for CoBuddy, Perceptron Mk1 and Solar Pro 4 yet, so there is no like-for-like coding score. Test both on a sample of your own tasks. Note that Perceptron Mk1 does not support tool calling, which most coding agents need.

Which has the bigger context window?

Solar Pro 4 has the largest context window at 524,288 tokens, against 131,072 for CoBuddy and 32,768 for Perceptron Mk1. Maximum output per response: CoBuddy up to 65,536, Perceptron Mk1 up to 8,192, Solar Pro 4 up to 131,072 tokens.

Which can read images, PDFs, audio or video?

CoBuddy accepts text; Perceptron Mk1 accepts text, images and video; Solar Pro 4 accepts text. Perceptron Mk1 handles the widest range of inputs.

Are any of these open source?

No. CoBuddy, Perceptron Mk1 and Solar Pro 4 are proprietary and only available through APIs and apps.

Which is newer?

Solar Pro 4 is the newest, released Aug 6, 2026. Perceptron Mk1 came out May 12, 2026; CoBuddy came out May 6, 2026. Knowledge cutoff: Solar Pro 4 Feb 2026.

How do you decide the winner?

Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Nov 2, 2026.