deepseek-ai/deepseek-harness · error · Error

ToolResultPruneConfig: headChars + marker + tailChars (${emi

Error message

ToolResultPruneConfig: headChars + marker + tailChars (${emittedChars}) must be at most thresholdChars (${resolved.thresholdChars})

What it means

Error "ToolResultPruneConfig: headChars + marker + tailChars (${emittedChars}) must be at most thresholdChars (${resolved.thresholdChars})" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/compaction/compaction-tool-result-pruner/src/config.ts:59

        + '(allowed: thresholdChars, headChars, tailChars)',
      )
    }
  }

  const resolved: ResolvedConfig = {
    thresholdChars: config.thresholdChars ?? DEFAULTS.thresholdChars,
    headChars: config.headChars ?? DEFAULTS.headChars,
    tailChars: config.tailChars ?? DEFAULTS.tailChars,
  }
  assertPositiveInteger('thresholdChars', resolved.thresholdChars)
  assertNonNegativeInteger('headChars', resolved.headChars)
  assertNonNegativeInteger('tailChars', resolved.tailChars)

  const emittedChars = resolved.headChars
    + codePointLength(PRUNE_MARKER)
    + resolved.tailChars
  if (emittedChars > resolved.thresholdChars) {
    throw new Error(
      `ToolResultPruneConfig: headChars + marker + tailChars (${emittedChars}) `
      + `must be at most thresholdChars (${resolved.thresholdChars})`,
    )
  }
  return deepFreeze(structuredClone(resolved))
}

function assertPositiveInteger(name: string, value: number): void {
  if (!Number.isInteger(value) || value <= 0) {
    throw new Error(`ToolResultPruneConfig: ${name} (${value}) must be a positive integer`)
  }
}

function assertNonNegativeInteger(name: string, value: number): void {
  if (!Number.isInteger(value) || value < 0) {
    throw new Error(`ToolResultPruneConfig: ${name} (${value}) must be a non-negative integer`)
  }
}

View on GitHub (pinned to b150a551b8)

Solutions

1. Raise thresholdChars or lower headChars and tailChars so they fit with the marker.

When it happens

Trigger: Thrown at packages/compaction/compaction-tool-result-pruner/src/config.ts:59 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/44d3e067033bef24. Report an issue: GitHub.