Plugin SDK defineToolPlugin helper

The entry helper for plugins that only add agent tools. Part of the Plugin entry points reference.

defineToolPlugin

Import: openclaw/plugin-sdk/tool-plugin

For plugins that only add agent tools. Keeps the source small, infers config and tool-parameter types from TypeBox schemas, wraps plain return values in the OpenClaw tool-result format, and exposes static metadata that openclaw plugins build writes into the plugin manifest (contracts.tools, configSchema).

import { Type } from "typebox";
import { defineToolPlugin } from "openclaw/plugin-sdk/tool-plugin";

export default defineToolPlugin({
  id: "stock-quotes",
  name: "Stock Quotes",
  description: "Fetch stock quotes.",
  configSchema: Type.Object({
    apiKey: Type.Optional(Type.String({ description: "API key." })),
  }),
  tools: (tool) => [
    tool({
      name: "quote",
      label: "Quote",
      description: "Fetch a quote.",
      parameters: Type.Object({
        symbol: Type.String({ description: "Ticker symbol." }),
      }),
      outputSchema: Type.Object(
        {
          symbol: Type.String(),
          hasKey: Type.Boolean(),
        },
        { additionalProperties: false },
      ),
      execute: async ({ symbol }, config) => ({ symbol, hasKey: Boolean(config.apiKey) }),
    }),
  ],
});

• configSchema is optional; omitting it uses a strict empty object schema (the generated manifest still includes configSchema).
• execute returns a plain string or JSON-serializable value; the helper wraps it as a text tool result with details set to the original (unstringified) return value.
• outputSchema optionally describes that original details value for Code Mode and Tool Search. Catalog calls reject an invalid schema before execution and validate the final value before returning it.
• For custom tool results, openclaw/plugin-sdk/tool-results exports textResult and jsonResult.
• Tool names are static, so openclaw plugins build derives contracts.tools from the declared tools without hand-duplicated names.
• Runtime loading stays strict: installed plugins still need openclaw.plugin.json and package.json openclaw.extensions. OpenClaw never executes plugin code to infer missing manifest data.

Input-dependent output schemas

The existing outputSchema field supports action-specific Code Mode results through the versioned x-openclaw-input-discriminator JSON Schema annotation. Construct the union and mapping from the same local variants using standard TypeBox APIs:

const variants = Object.entries({
  list: Type.Object({ items: Type.Array(Type.String()) }),
  status: Type.Object({ ready: Type.Boolean() }),
});
const outputSchema = Type.Union(
  variants.map(([, schema]) => schema),
  {
    "x-openclaw-input-discriminator": {
      version: 1,
      inputProperty: "action",
      mapping: Object.fromEntries(variants.map(([value], index) => [value, index])),
    },
  },
);

Use the result as outputSchema in defineToolPlugin or api.registerTool. Include success and non-throwing failure outcomes in each variant. Static metadata preserves the annotation. Code Mode infers the selected return type; Tool Search validates the actual and originally advertised operation results. Missing or broad selectors retain a sound union. Reference-bearing schemas and declarations that exceed existing bounds use the conservative umbrella contract. See Input-dependent outputs for version, hook, and validation behavior.