Context & Metadata

Context truncation

Instead of returning an error for prompts that exceed the context window, truncate gracefully:

response = client.chat.completions.create(
    model="forii/deepseek-v3",
    messages=long_messages,
    context_length_exceeded_behavior="truncate",  # or "error"
    max_tokens=2048,
)

Value	Behavior
`"truncate"`	Truncate the prompt to fit the context window. Process continues normally.
`"error"`	Return an error if the prompt exceeds the context limit.

truncate is the default. It removes the oldest messages first (system message preserved), giving you a better UX than a hard error. Use "error" when you need to know exactly when context limits are hit.

Request metadata

Attach key-value metadata for cost attribution across teams and projects:

response = client.chat.completions.create(
    model="forii/deepseek-v3",
    messages=[{"role": "user", "content": "Hello"}],
    extra_body={"metadata": {
        "user_id": "u_12345",
        "session_id": "s_abc",
        "team": "search",
        "project": "ranker",
    }},
)

Metadata appears in usage logs and the usage API, letting you attribute costs to specific teams, projects, or users.

Metadata is a Forii extension adopted from Fireworks’ parameters. Values must be strings. Useful for cost attribution, A/B test labeling, and debugging.

Additional Forii extensions

Parameter	Type	Description
`reasoning_effort`	string	`none` \| `low` \| `medium` \| `high` — see Reasoning Models
`context_length_exceeded_behavior`	string	`"truncate"` (default) or `"error"`
`repetition_penalty`	float	0–2, applies to both prompt and output
`top_k`	integer	Top-K sampling
`metadata`	object	Key-value string metadata for tracing and cost attribution

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Context truncation

Request metadata

Additional Forii extensions

​Context truncation

​Request metadata

​Additional Forii extensions

Context truncation

Request metadata

Additional Forii extensions