GLM-5.2 vs Claude Fable 5 실측: 출력 예산, reasoning_tokens, 그리고 0.8 가격 계수
Crazyrouter OpenAI 호환 API에서 glm-5.2와 claude-fable-5를 수학, 물리, Canvas 애니메이션 과제로 비교하고, glm-5.2의 현재 0.8 discount 정보를 함께 정리합니다.

GLM-5.2 vs Claude Fable 5: 차이는 모델 능력보다 출력 예산에서 먼저 드러났다#
이번 글은 단순한 승패표가 아닙니다. 실제 API 호출에서 GLM-5.2는 출력 예산을 늘리면 수학과 물리 문제를 맞혔지만, 낮은 예산에서는 보이는 본문이 비는 경우가 있었습니다. Claude Fable 5는 같은 조건에서 더 짧고 안정적이었고, 긴 HTML 애니메이션 과제에서는 더 완성도가 높았습니다.

이 테스트가 필요한 이유#
The test used the Crazyrouter OpenAI-compatible API rather than a chat UI. That matters because the result was not judged only by prose quality. Each response was checked with operational metadata:
Base URL: https://cn.crazyrouter.com/v1
Endpoint: POST /v1/chat/completions
Models: glm-5.2, claude-fable-5
temperature: 0.2
Test date: 2026-07-06
The important fields were max_tokens, completion_tokens, reasoning_tokens, finish_reason, visible content length, whether the generated HTML was closed, and whether the animation actually moved in a browser.
테스트 설계#
The benchmark deliberately mixed three task types:
| Task | Purpose | Reference result |
|---|---|---|
MATH-003 | State-based expectation reasoning | Expected flips until HH = 6 |
PHYS-003 | Momentum plus energy accounting | V = 3.0 m/s, x ≈ 0.148 m |
CODE-003-ANIM | Long runnable artifact generation | Complete 800x500 Canvas animation HTML |
The first two tasks measured reasoning. The third task measured whether a model can produce a complete artifact, not merely a convincing partial code block.
관찰된 결과#
| Task | glm-5.2 | claude-fable-5 |
|---|---|---|
| Math, original budget | finish_reason=length, completion_tokens=1601, reasoning_tokens=1600, visible body empty | finish_reason=stop, complete and correct |
| Math, retest | Correct after max_tokens=3200 | Retest not needed |
| Physics, original budget | finish_reason=length, visible body empty | Complete and correct |
| Physics, retest | Correct after max_tokens=8000 | Retest not needed |
| Animation, original budget | Empty visible HTML at max_tokens=3200 | Partial HTML, truncated |
| Animation, retest | Still truncated at max_tokens=8000 | Complete HTML; browser validation passed |
The most important observation is that GLM-5.2 was not failing the reasoning itself. In the math and physics tasks, it produced correct answers after a larger output budget. The problem was visibility and completion: a request could return HTTP 200 while the user-facing content was empty or incomplete.
For the long Canvas animation, the difference was sharper. GLM-5.2 produced a visible HTML fragment at max_tokens=8000, but it stopped inside JavaScript and did not close the file. Claude Fable 5 completed the HTML at max_tokens=8000; browser validation showed no console errors, an 800x500 canvas, controls, a speed slider, and changedPixels=55090 after 700 ms.
비용 대비 성능#
작성 시점 Crazyrouter pricing API는 glm-5.2에 대해 discount: 0.8을 반환합니다. 따라서 reasoning_tokens와 max_tokens를 운영 지표로 관리할 수 있다면 GLM-5.2는 비용 대비 매력적인 선택지가 됩니다.
This is the practical tradeoff:
| Workload | Better fit from this test |
|---|---|
| Short reasoning with enough output budget | GLM-5.2 can be a cost-effective option |
| Low-budget reasoning responses | Claude Fable 5 was steadier |
| Long single-file code generation | Claude Fable 5 was stronger in this run |
| Batch evaluations where metadata is logged | GLM-5.2 becomes easier to operate safely |
Do not treat the 0.8 multiplier as a permanent universal price. It is a pricing-data snapshot from Crazyrouter at publication time and should be checked again before a large deployment.
연동 시 체크포인트#
Minimal request:
curl https://cn.crazyrouter.com/v1/chat/completions \
-H "Authorization: Bearer $CRAZYROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "glm-5.2",
"messages": [
{
"role": "user",
"content": "Solve the HH expected-flips problem with state equations."
}
],
"temperature": 0.2,
"max_tokens": 3200
}'
To compare Claude Fable 5, keep the same payload and change only the model:
{
"model": "claude-fable-5"
}
For production-style evaluations, log this shape for every request:
{
"model": "glm-5.2",
"max_tokens": 3200,
"finish_reason": "length",
"completion_tokens": 3200,
"reasoning_tokens": 3178,
"visible_content_chars": 0,
"html_closed": false,
"browser_validation": "not_run_incomplete_html"
}
API endpoints should stay clean. Do not add UTM parameters to https://cn.crazyrouter.com/v1. Use tracking only on human-facing article or registration links.
Crazyrouter의 OpenAI 호환 엔드포인트에서 같은 요청을 실행해 본인 업무에 맞는 결과를 직접 비교할 수 있습니다.
FAQ#
Did GLM-5.2 fail the reasoning tasks?#
No. In this run, GLM-5.2 solved the math task after max_tokens=3200 and the physics task after max_tokens=8000. The issue was that lower budgets were consumed mostly by reasoning tokens before visible content appeared.
Why not score HTTP 200 as success?#
Because HTTP 200 only means the API call returned. A benchmark answer can still be unusable if finish_reason=length, visible content is empty, or generated code is incomplete.
Why was the animation task included?#
Long code generation exposes a different failure mode. A model can write a convincing first half of a file and still fail if the HTML or JavaScript is cut off.
Is GLM-5.2 still worth testing?#
Yes. The current 0.8 discount multiplier makes it attractive for workloads where you can allocate enough output budget and monitor response metadata.
What should be recorded in future comparisons?#
At minimum: max_tokens, completion_tokens, reasoning_tokens, finish_reason, visible output length, artifact completeness, and runtime validation.
Final verdict#
요약하면 GLM-5.2는 가격 면에서 강점이 있고 추론도 가능하지만 출력 예산 관리가 필수입니다. Claude Fable 5는 낮은 예산과 긴 단일 파일 코드 생성에서 더 안정적이었습니다.




