Bug type

Behavior bug (incorrect output/state without crash)

Beta release blocker

No

Summary

OpenAI-compatible chat-completions models configured with compat.supportsTools: false still receive a tools payload when OpenClaw has tools available.

Steps to reproduce

1. Install the OpenClaw beta package [email protected] or its dependency @mariozechner/[email protected].
2. Configure an OpenAI-compatible chat-completions model with compat.supportsTools: false.
3. Run a request where OpenClaw has at least one tool in context.tools.
4. Inspect the outbound chat-completions payload before network send.

Minimal payload-capture repro against @mariozechner/[email protected]:

TMP=$(mktemp -d)
cd "$TMP"
npm init -y >/dev/null
npm install @mariozechner/[email protected] >/dev/null
node --input-type=module <<'NODE'
import { streamOpenAICompletions } from '@mariozechner/pi-ai/openai-completions';

const model = {
  api: 'openai-completions',
  provider: 'venice',
  id: 'chat-only-model',
  baseUrl: 'https://example.invalid/v1',
  input: ['text'],
  compat: { supportsTools: false },
};

const context = {
  systemPrompt: 'test',
  messages: [{ role: 'user', content: 'hello' }],
  tools: [
    {
      name: 'noop',
      description: 'noop tool',
      parameters: { type: 'object', properties: {} },
    },
  ],
};

const stream = streamOpenAICompletions(model, context, {
  apiKey: 'x',
  onPayload(params) {
    console.log(JSON.stringify({ hasTools: Object.hasOwn(params, 'tools'), tools: params.tools }, null, 2));
    throw new Error('stop after payload capture');
  },
});

for await (const event of stream) {
  if (event.type === 'error') console.log(event.error.errorMessage);
}
NODE

Expected behavior

When a model is configured with compat.supportsTools: false, the OpenAI-compatible chat-completions payload should not include tools, and tool-history fallback handling should also avoid injecting tools: [].

Actual behavior

The captured payload includes tools even though the model compat explicitly sets supportsTools: false:

{
  "hasTools": true,
  "tools": [
    {
      "type": "function",
      "function": {
        "name": "noop",
        "description": "noop tool",
        "parameters": {
          "type": "object",
          "properties": {}
        },
        "strict": false
      }
    }
  ]
}

The process then stops because the repro intentionally throws after capturing onPayload.

OpenClaw version

2026.4.27-beta.1

Operating system

Ubuntu 24.04 / Linux

Install method

npm package / npm global beta path; isolated repro installed @mariozechner/[email protected], which [email protected] depends on.

Model

OpenAI-compatible chat-completions model with compat.supportsTools: false.

Provider / routing chain

OpenClaw -> @mariozechner/pi-ai openai-completions provider -> OpenAI-compatible endpoint.

Additional provider/model setup details

Observed while using chat-only OpenAI-compatible providers that reject tool schemas. The repro uses a synthetic provider: 'venice' model object only to capture the generated payload before network send; no provider credentials are required.

Logs, screenshots, and evidence

$ npm view [email protected] dependencies.@mariozechner/pi-ai
0.70.5

$ npm view @mariozechner/[email protected] version
0.70.5

# Repro output:
{
  "hasTools": true,
  "tools": [
    {
      "type": "function",
      "function": {
        "name": "noop",
        "description": "noop tool",
        "parameters": {
          "type": "object",
          "properties": {}
        },
        "strict": false
      }
    }
  ]
}
stop after payload capture

Package inspection also shows that buildParams() gates on context.tools but not on compat.supportsTools, and getCompat() does not merge a supportsTools field from model.compat.

Impact and severity

Affected: users of OpenAI-compatible chat-completions providers/models that do not support tools.

Severity: High for those providers, because any run with available tools can send an unsupported tools field and fail before the model can answer.

Frequency: Always reproduced for the payload path above when context.tools is non-empty.

Consequence: Chat-only provider runs fail or require local patching/config workarounds even when the model is explicitly marked as not supporting tools.

Additional information

A local downstream patch fixes this by adding supportsTools to the OpenAI-compatible compat object, merging model.compat.supportsTools, and guarding both context.tools emission and the tool-history tools: [] fallback with compat.supportsTools !== false.