Last refreshed 2026-09-01. Next refresh: weekly.
Why use Claude Fable 5.1 on GCP Vertex AI?
GCP Vertex AI offers Claude Fable 5.1 with pay-as-you-go pricing at $10.00/1M input tokens. Vertex AI is Google Cloud's managed AI platform, offering access to Gemini models and hundreds of partner models alongside tools for fine-tuning, grounding, vector search, and end-to-end MLOps pipelines.
Compare Claude Fable 5.1 across 4 providers to find the best fit for your use caseSetup recipe
Python + curlpip install google-cloud-aiplatformexport GOOGLE_CLOUD_PROJECT=...import os
import vertexai
from vertexai.generative_models import GenerativeModel
vertexai.init(project=os.environ["GOOGLE_CLOUD_PROJECT"], location="us-central1")claude-fable-5-1Request example
import os
import vertexai
from vertexai.generative_models import GenerativeModel
# Reads GOOGLE_CLOUD_PROJECT from env; authenticates via Application Default Credentials
vertexai.init(project=os.environ["GOOGLE_CLOUD_PROJECT"], location="us-central1")
model = GenerativeModel("claude-fable-5-1")
response = model.generate_content("Hello")
print(response.text)Gotchas
- For Google-published models use the model name directly, e.g. "gemini-2.0-flash-001". For third-party publishers (Anthropic, Meta, etc.) use the full publisher path, e.g. "publishers/anthropic/models/claude-3-5-sonnet-v2@20241022".
- The examples expect GOOGLE_CLOUD_PROJECT; rename it only if your application config maps the new variable.
Compare Claude Fable 5.1 Across Providers
| Provider | Input (per 1M) | Output (per 1M) |
|---|---|---|
| Anthropic | $10.00 | $50.00 |
| AWS Bedrock | $10.00 | $50.00 |
| GCP Vertex AI | $10.00 | $50.00 |
| Microsoft Foundry | $10.00 | $50.00 |
Pricing
| Type | Price (per 1M) |
|---|---|
| Input tokens | $10.00 |
| Output tokens | $50.00 |
Capabilities
About Claude Fable 5.1
Anthropic's generally available Mythos-class model for demanding reasoning, long-horizon agents, and ambitious coding, released September 1, 2026. Same underlying model as Claude Mythos 5.1 with cybersecurity and biology safeguards (flagged queries route to Opus 4.8 for cyber and Opus 5 for biology; those reroutes are not billed at Fable prices). Claude API id claude-fable-5-1. List price $10 per 1M input tokens and $50 per 1M output tokens; cache reads $0.25 per 1M (0.025x base input, 75% less than Fable 5's $1.00).