AI Providers
Anthropic (Claude)
Claude 3.5 Sonnet, Haiku, and Opus — especially good for long-form writing.
Anthropic's Claude models are often preferred for long-form writing: blog posts, scripts, reports, and anything where tone and reasoning matter. Claude does not have a free tier; you'll need billing set up.
Get a key
- Go to console.anthropic.com/settings/keys
- Sign in and add billing ($5 minimum)
- Click Create Key
- Name it and copy — starts with
sk-ant-
Models available in ContentAI
| Model | Context | Best for |
|---|---|---|
claude-3-5-sonnet-20241022 | 200k | ⭐ Default — best for long-form writing |
claude-3-5-haiku-20241022 | 200k | Cheaper, faster, still high-quality |
claude-3-opus-20240229 | 200k | Highest reasoning quality, slower |
Claude charges per million tokens; see anthropic.com/pricing for live numbers.
Why users pick Claude
- Writes naturally. Claude tends to produce prose that needs less editing.
- Long context, reliably. 200k-token context with minimal quality degradation at length.
- Careful with tone. When you say "professional but warm," Claude tends to actually do it.
- Refuses less than GPT. For creative writing or tough personas, Claude is often more cooperative.
Setup in ContentAI
- Settings → Anthropic card → paste key
- Pick claude-3-5-sonnet-20241022
- Click Test
- (Optional) Set as active provider
When to use which Claude model
| Use case | Best model |
|---|---|
| Blog posts, newsletters, long emails | Claude 3.5 Sonnet |
| Quick rewrites, short captions | Claude 3.5 Haiku |
| Strategic documents, complex outlines | Claude 3 Opus |
Common errors
| Error | Fix |
|---|---|
authentication_error: invalid x-api-key | Key wrong or revoked |
permission_error: Your account doesn't have access... | Upgrade tier or pick a different model |
rate_limit_error | Wait a moment |
overloaded_error | Claude is under load — retry in a few seconds |
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