PR #77230: fix(mcp): normalize parameter-free tool inputSchema for OpenAI (#77043)

• Repository: openclaw/openclaw
• Author: SymbolStar
• State: open | merged: False
• Link: https://github.com/openclaw/openclaw/pull/77230

Description (problem / solution / changelog)

Fixes #77043

Problem

Bundle MCP tools created in pi-bundle-mcp-materialize.ts were assigned raw inputSchema from MCP servers without normalization. Unlike plugin tools (which pass through normalizeToolParameters in pi-tools.ts) and the provider-level normalizeOpenAIToolSchemas hook, bundle MCP tools were appended to effectiveTools after all normalization steps in attempt.ts:1115.

When an MCP server returns a parameter-free tool with inputSchema: {} or {type: "object"} (missing properties), OpenAI rejects it with:

400 Invalid schema for function 'flux-mcp__get_flux_instance': In context=(), object schema missing properties.

Fix

Apply normalizeToolParameterSchema to bundle MCP tool inputSchema at materialization time, ensuring empty/incomplete schemas are promoted to {type: "object", properties: {}}.

Root Cause (same as #75362 / #60158)

The previous fixes (#60176, #75401) addressed this for plugin tools and the OpenAI provider hook, but the bundle MCP materialization path was missed — it assigns parameters: tool.inputSchema directly without normalization, and these tools are combined with already-normalized tools after the normalization pipeline runs.

Test

Added pi-bundle-mcp-materialize.schema.test.ts covering:

• Empty schema {} → {type: "object", properties: {}}
• {type: "object"} without properties → adds properties: {}
• undefined/null inputSchema → {type: "object", properties: {}}
• Valid schemas with properties preserved unchanged

Changed files

• src/agents/pi-bundle-mcp-materialize.schema.test.ts (added, +68/-0)
• src/agents/pi-bundle-mcp-materialize.ts (modified, +2/-1)