Tool call audit log for the Vercel AI SDK

Pass your tools through wrapTools and each execute call is written as a signed, chained record: a decision before the tool runs and an outcome after it. TypeScript and JavaScript.

Full steps: Vercel AI SDK quickstart. What recording covers and where it stops: Tool coverage.

The change #

One call where generateText or streamText gets its tools. wrapTools takes the object you already pass, and each key is the recorded tool name. The ai package is not a dependency of the SDK.

TypeScript

import { wrapTools } from "signafaide";
import { generateText, stepCountIs } from "ai";

const tools = wrapTools(
  { lookup_order: lookupOrder, refund },
  { agent: "support-bot" },
);

const result = await generateText({
  model,
  tools,
  stopWhen: stepCountIs(3),
  prompt: "Refund order A-1001",
});

A verify run #

Run the agent once, then npx signafaide verify. This is a local run in which the model asked for refund once: three records for the tool list, one decision and one outcome.

$ npx signafaide verify
local state: /home/dev/support-agent/.signafaide
 1. Envelope schema              PASS         5 records
 2. Record hashes                NOT CHECKED  0 records; 5 not yet shipped (no receipt); nothing co-signed yet
 3. Client signatures            PASS         5 records
 4. Agent chains                 PASS         5 records
 5. Merkle proofs                NOT CHECKED  0 records; nothing co-signed yet
 6. Batch hashes and signatures  NOT CHECKED  0 batches; nothing co-signed yet
 7. Batch chain                  NOT CHECKED  0 batches; nothing co-signed yet
 8. Signed heads                 NOT CHECKED  0 heads; nothing co-signed yet
 9. drand rounds                 NOT CHECKED  0 rounds
10. Anchors                      NOT CHECKED  0 anchors; local state holds no anchors
11. OpenTimestamps               NOT CHECKED  0 proofs
12. Content hashes               PASS         5 records
coverage: _pending/nokey/support-bot: all 2 declared tools are recorded
checked here: signatures, chain links and content hashes of all 5 records, using this machine's keys
co-signature, public timestamp: not yet. Run `signafaide init` to send hashes, or self-host (SIGNAFAIDE_URL)
PASS: 4 of 12 checks passed, 8 not checked (nothing co-signed yet)

What is recorded and what is not #

Recorded. Every execute(input) of a wrapped tool: the tool name and input, then the output or the error. Inputs and outputs stay in .signafaide/ on your machine. Nothing is sent until you run npx signafaide init, and then only salted hashes.
Not recorded. The options argument of execute (the messages and the abort signal) is not recorded. A tool with no execute function cannot be wrapped, and a tool you did not wrap leaves no record. Give the full list to declareTools and signafaide verify names the tools that are not recorded.
Evidence, not certification. Records prove integrity and timing, not that a decision was right. The eight checks not run above need a witness: the co-signature and the public timestamp come after npx signafaide init.

Next: install, wrap, verify and send hashes, step by step. Vercel AI SDK quickstart