deepseek-ai/deepseek-harness · error · TypeError

tools/post-execute accept decision cannot replace both value

Error message

tools/post-execute accept decision cannot replace both value and content

What it means

Error "tools/post-execute accept decision cannot replace both value and content" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/core/tools/src/index.ts:1758

   * Runs inside `execute`'s outer try/catch (a throwing listener → isError).
   */
  private async postExecute(exec: ToolExecution, result: ToolExecutionResult): Promise<ToolExecutionResult> {
    const decision = await this.ctx.waterfall(
      scopeTarget(this, exec.agent), 'tools/post-execute', exec, result,
      () => Promise.resolve<PostToolDecision>({ kind: 'accept' }),
    )
    const decisionContexts = decision.additionalContexts ?? []
    if (decision.kind === 'block') {
      const message = failureMessageFromContent(decision.feedback)
      return this.markCanonical(exec, {
        content: decision.feedback,
        isError: true,
        error: { message },
        ...decisionContexts.length > 0 ? { additionalContexts: decisionContexts } : {},
      })
    }
    if (Object.hasOwn(decision, 'content') && Object.hasOwn(decision, 'value')) {
      throw new TypeError('tools/post-execute accept decision cannot replace both value and content')
    }
    const additionalContexts = [
      ...result.additionalContexts ?? [],
      ...decisionContexts,
    ]
    if (Object.hasOwn(decision, 'value')) {
      if (result.isError) {
        throw new TypeError('tools/post-execute cannot replace the value of a failed result')
      }
      const tool = this.resolveExecution(exec.name, exec.agent, exec.parent !== undefined)
      if (tool === undefined) throw new ToolNotFoundError(exec.name)
      const replaced = this.createSuccessResult(exec, tool, decision.value)
      return this.markCanonical(exec, {
        ...replaced,
        ...additionalContexts.length > 0 ? { additionalContexts } : {},
      })
    }
    return this.markCanonical(exec, {

View on GitHub (pinned to b150a551b8)

When it happens

Trigger: Thrown at packages/core/tools/src/index.ts:1758 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/082a56e38c3fec5b. Report an issue: GitHub.