deepseek-ai/deepseek-harness · error · Error

tool name "${RUN_CODE_NAME}" is reserved for the Code Mode p

Error message

tool name "${RUN_CODE_NAME}" is reserved for the Code Mode presentation transport and cannot be registered or shadowed

What it means

Error "tool name "${RUN_CODE_NAME}" is reserved for the Code Mode presentation transport and cannot be registered or shadowed" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/core/tools/src/index.ts:1055

  register(definition: ToolDefinition): () => void {
    const name = definition.name
    const output = (definition as Partial<ToolDefinition>).output
    if (output === undefined || typeof output !== 'object'
      || typeof output.render !== 'function'
      || (output.presentationMeta !== undefined && typeof output.presentationMeta !== 'function')) {
      throw new TypeError(`tool "${name}" must declare output { schema, render, presentationMeta? }`)
    }
    assertSupportedJsonSchema(output.schema)
    const timeoutMs = definition.timeoutMs
    if (timeoutMs !== undefined
      && (!Number.isFinite(timeoutMs) || timeoutMs <= 0)) {
      throw new TypeError(`tool "${name}" timeoutMs must be a positive finite number`)
    }
    // Reserved unconditionally: any agent may select a code mode for itself,
    // so a name free to take under the deployment default would become a
    // collision the moment a preset mounted.
    if (name === RUN_CODE_NAME) {
      throw new Error(`tool name "${RUN_CODE_NAME}" is reserved for the Code Mode presentation transport and cannot be registered or shadowed`)
    }
    return this.layers.effect(
      this.ctx,
      layer => layer.tools.insert(name, definition),
      { label: 'tools.register()' },
    )
  }

  /**
   * Restrict global tools for the calling agent scope. Empty filters, unknown
   * names, scope-local names, and reserved transport names fail. Restrictions
   * intersect; scoped registrations remain visible.
   * @param filter - global-tool mask: `allow` (keep only) and/or `deny` (remove).
   * @returns the exact disposer that lifts this restriction.
   */
  restrict(filter: ToolRestriction): () => void {
    const scope = scopeOf(this.ctx)
    if (scope === undefined) {

View on GitHub (pinned to b150a551b8)

When it happens

Trigger: Thrown at packages/core/tools/src/index.ts:1055 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/b425f41e632e6ff3. Report an issue: GitHub.