deepseek-ai/deepseek-harness · error · Error

tools.presentAs("${mode}") conflicts with "${layer.mode}" al

Error message

tools.presentAs("${mode}") conflicts with "${layer.mode}" already declared for this scope; one composition selects one presentation

What it means

Error "tools.presentAs("${mode}") conflicts with "${layer.mode}" already declared for this scope; one composition selects one presentation" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/core/tools/src/index.ts:956

   * declaration covers every agent joined under it.
   *
   * Scoped only, and one declaration per scope: this is how an agent preset
   * composes Code Mode agents beside native ones in the same process, and a
   * process-global override would be the `mode` config field instead.
   * @param mode - the presentation the covered agents' models see.
   * @returns the exact disposer that restores the deployment default.
   */
  presentAs(mode: ToolPresentationMode): () => void {
    const ctx = this.ctx
    if (scopeOf(ctx) === undefined) {
      throw new Error('tools.presentAs() requires a scoped context (agent.ctx): a context-global presentation is the `mode` config field on the tools row')
    }
    const dispose = ctx.effect(function* (this: ToolRuntime) {
      yield this.layers.effect(
        ctx,
        (layer) => {
          if (layer.mode !== undefined) {
            throw new Error(`tools.presentAs("${mode}") conflicts with "${layer.mode}" already declared for this scope; one composition selects one presentation`)
          }
          layer.mode = mode
          return () => { layer.mode = undefined }
        },
        { label: 'tools.presentAs()' },
      )
      // The SDK and collapse sections are per scope for the same reason the
      // mode is. Under a deployment that already defaults to a code mode this
      // shadows the global registration with an identical body, which costs
      // nothing and keeps one rule instead of a case analysis.
      if (mode !== 'native') {
        yield ctx.systemPrompt.section(this.collapseSection())
        yield ctx.systemPrompt.section(this.sdkSection())
      }
    }.bind(this), 'tools.presentAs()')
    // oxlint-disable-next-line typescript/no-misused-promises -- synchronous composite teardown; direct return preserves disposer identity
    return dispose
  }

View on GitHub (pinned to b150a551b8)

When it happens

Trigger: Thrown at packages/core/tools/src/index.ts:956 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/715b8f7cd729544c. Report an issue: GitHub.