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bmel:truncateToTokens

Category: LLM & AI Observability · Returns: bmel:string

bmel:truncateToTokens(text: bmel:string, maxTokens: bmel:integer, tokenizer: bmel:string)

Description

Truncates a string to at most maxTokens tokens using the specified tokenizer, cutting at a word boundary where possible. Useful for capping prompt or context size before sending to an LLM, and for enforcing context-window budgets in telemetry frames. Uses the same tokenizer identifiers as bmel:tokenCount.

Arguments

Parameter Type Required Description
text bmel:string The input text to truncate.
maxTokens bmel:integer Maximum number of tokens to keep.
tokenizer bmel:string Tokenizer identifier. Supported values: 'cl100k_base', 'o200k_base', 'p50k_base', 'voyage', 'gemini', 'llama3', 'mistral'.

Example

bmel:truncateToTokens({createChat:Request Payload}.$.message, 4096, 'cl100k_base')

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