| name | acture-ai |
| description | Build an AI-tool-calling consumer surface in a target project — project the command registry as LLM function-calling tool definitions so a model can invoke commands. Covers the SDK choice (Vercel AI SDK / Anthropic SDK / OpenAI SDK / LangChain), the schema-projection fork (pass Zod through vs project to JSON Schema), the agent-written vs `acture-ai-vercel` package paths, errors-as-data, and the prompt-injection guardrails. Use when exposing a command-dispatch app to an LLM, or when working ON the `acture-ai-vercel` package. Triggers on "AI tool calling", "LLM function calling", "tool use", "expose commands to an AI", "Vercel AI SDK", "streamText tools", "let the model call commands", "AI agent loop". |
acture ai — the registry as LLM tool definitions
LLM function calling needs exactly the metadata a command registry already carries: a name, a description, and a parameter schema. The Vercel AI SDK's tool({ description, parameters, execute }), the Anthropic and OpenAI tool-use APIs, and LangChain all converge on this shape (journal article §3.2). Projecting a registry as AI tools is a thin adapter that iterates the registry and emits per-tool definitions — the same registry, a different projection.
Load acture-consumer-integration first. AI tool calling is a consumer — this skill covers AI specifics; the foundational pattern (the dev-tool-first rule, the per-consumer hand-write-vs-install choice, the tool-library-is-the-user's-choice rule) lives there.
Two decisions to surface (per acture-consumer-integration)
Decision 1 — the AI SDK (the tool-library choice — the user's)
AI tool calling rests on an SDK. Realistic choices: Vercel AI SDK, the Anthropic SDK, the OpenAI SDK, LangChain, or a direct provider HTTP call. This choice belongs to the project, not to acture. acture ships one tested per-tool binding — acture-ai-vercel, built on the Vercel AI SDK — for projects that chose it. It does not imply the Vercel SDK is the only option.
The SDK choice drives a real implementation fork — how the parameter schema is projected:
- SDKs that accept a schema library object directly (Vercel AI SDK, LangChain) — pass
record.params (the Zod schema) through unchanged. This preserves z.refine / z.transform validators that JSON Schema would silently drop.
- SDKs that want JSON Schema on the wire (raw Anthropic / OpenAI tool definitions) — project through
toJsonSchema(record) and put the result in input_schema / parameters.
Name this fork explicitly when you surface the SDK choice — it changes the adapter's core line.
Decision 2 — agent-written vs package-reuse
- Agent-written — write the projection directly: iterate
registry.list({ tiers }), build the SDK's tool-definition shape per command, and give each an execute that routes through registry.dispatch. ~30 lines, owned. This is the only path if the SDK is not the Vercel AI SDK — adapt the pattern in packages/ai-vercel/src/index.ts (a worked example, not an import).
- Package-reuse — only if the SDK is the Vercel AI SDK — install
acture-ai-vercel. toAITools(registry, { tiers?, excludeFunctionWhen?, context?, onDispatched? }) returns Record<string, Tool> ready to drop into streamText({ tools }) / generateText({ tools }). Cost: a dependency to track (ai and zod are peer deps).
Surface both; follow a stated preference if one exists; otherwise ask. Record the choice in the project's adoption notes.
The build — what every path produces, and what to get right
execute routes through registry.dispatch — always. The tool's execute(args) calls registry.dispatch(id, args, ctx); it never invokes a handler directly. This is what gives the model the same validation and middleware as every other surface.- Errors are data.
execute resolves to { ok: true, value } on success and { ok: false, error: { code, message, details } } on failure — never throws. The model sees the error in the tool-result message and can recover. This is the same shape the model sees on every surface (palette, hotkeys, MCP) — do not invent a per-surface error format.
- Tier filtering is a parameterized projection, not adapter logic. Default
tiers: ['stable']; experimental opt-in; internal never exposed. This is core's registry.list({ tiers }) — the adapter passes the option through (hard-don't #3).
@deprecated → a deterministic banner. A deprecated-tier command's description is prefixed [DEPRECATED — <reason>] so the model sees the deprecation before composing a tool call. This banner is the one description rewrite the adapter is allowed — and it mirrors acture-mcp-server exactly.- Function
when-clauses are skipped by default (excludeFunctionWhen: true) — a function when is opaque to static projection and unsafe to expose to a model as available.
- An AI multi-step sequence IS a macro. When the model composes a chain of tool calls, its output is structurally a
{commandId, params} sequence — the same shape as a recorded macro (journal §3.2, §3.7). If the project also has a macros surface, the AI-emitted format and the recorded-macro format are one format; load acture-macros and do not invent a second one.
The security guardrails — this surface takes input from a model
The LLM is an untrusted caller. The prompt-injection / tool-poisoning attack class applies directly (hard-don'ts #5 and #10):
- The LLM proposes; the registry decides.
execute routes the model's (name, args) through registry.dispatch — Map.get(name) + schema validation. Never eval, new Function, or reflective invocation of a model-supplied string.
- Schema validation happens at the dispatcher, regardless of caller. There is no "this call came from the AI surface, so skip validation" fast path. The model's choice of function is not authorization.
- Authorization is a separate concern — a
when-clause or middleware, never the caller's identity. The model has zero special trust.
When working ON acture-ai-vercel
The same positioning applies inward (per acture-consumer-integration §"When you are working ON a consumer-specific package"):
ai and zod are peer dependencies, framed as the user's tool choice — named, not sold.- The package translates the registry to Vercel AI SDK tool definitions; it holds no business logic and makes no architectural decisions (hard-don't #3). The deprecation banner is the only allowed description rewrite, it is deterministic, and it mirrors
acture-mcp-server's.
- It passes
record.params (Zod) through directly rather than re-projecting — because the Vercel SDK accepts Zod. A JSON-Schema-wanting SDK adapter would project through toJsonSchema instead; that difference is per-SDK, not a core change.
- No agent loop, no orchestration, no prompt construction — those belong to the host. The package emits tool definitions and nothing more.
What NOT to build (wait for a real need)
No per-surface trust fast-path (hard-don't #10), no prompt-engineering or description-rewriting beyond the deprecation banner (that is business logic — hard-don't #3), no agent loop / multi-step orchestration in the adapter (the host owns that — maxSteps is the SDK's, not acture's), no acture-authored system prompt. Wait until a concrete need surfaces in the project. The registry → tool-definitions projection covers the overwhelming majority of AI-tool-calling needs. YAGNI applied softly.
See also
acture-consumer-integration — the foundational consumer pattern this builds on.acture-schema-bridge — toJsonSchema(record) and the JSON-Schema-representable subset rule; relevant when the SDK wants JSON Schema rather than Zod.acture-tier-system — tier semantics and what @deprecated does.acture-mcp — the sibling AI-facing surface; shares tier filtering, deprecation banners, function-when exclusion, and errors-as-data. MCP always projects to JSON Schema; AI SDKs may take Zod directly.acture-macros — an AI-composed tool-call sequence is a macro; share the format.packages/ai-vercel/src/index.ts — the Vercel AI SDK binding's source, a worked example to adapt for other SDKs.docs/command_dispatch_journal_article.md §3.2 — AI tool calling.
