@sema-agent/core/dist/core/park-selfcheck.js

Stateless, task-oriented AI agent core

import { boundInputHashOf, canonicalize } from "./canonical-json.js";
import { MAX_SUPPORTED_CHECKPOINT_VERSION, mintCheckpointId, mintCheckpointToken, resolveCheckpointStore } from "./checkpoint-store.js";
import { resolveDeclaredDurability } from "./wiring-manifest.js";
export const PARK_SELFCHECK_SCOPE_PREFIX = "sema:park-selfcheck:";
export const PARK_SELFCHECK_STEP_TIMEOUT_MS = 10_000;
export const PARK_SELFCHECK_ROW_TTL_MS = 60_000;
async function within(op, step) {
    let timer;
    try {
        return await Promise.race([
            Promise.resolve()
                .then(op)
                .then((ok) => ({ ok }))
                .catch((threw) => ({ threw })),
            new Promise((resolve) => {
                timer = setTimeout(() => resolve({ timedOut: `${step} did not answer within ${PARK_SELFCHECK_STEP_TIMEOUT_MS}ms — a store that neither answers nor errors is the failure this probe exists to surface, not one it may wait on` }), PARK_SELFCHECK_STEP_TIMEOUT_MS);
            }),
        ]);
    }
    finally {
        if (timer !== undefined)
            clearTimeout(timer);
    }
}
function declaresDurable(store, name) {
    try {
        return resolveDeclaredDurability(store, name) === "durable";
    }
    catch {
        return false;
    }
}
export function durableParkGapOf(halves) {
    if (!halves.checkpointWired)
        return undefined;
    if (halves.checkpointDurable && halves.sessionDurable)
        return undefined;
    if (halves.checkpointDurable && !halves.sessionDurable) {
        return ("this deployment wires a checkpoint store that declares durability but a session store that does not " +
            "(RunnerDeps.sessionStore — absent means the built-in in-memory store): a durable park needs BOTH halves, " +
            "so a parked approval survives the restart while the conversation it resumes into does not, and a resume " +
            "arriving afterwards finds the checkpoint and not the session");
    }
    if (!halves.checkpointDurable && halves.sessionDurable) {
        return ("this deployment wires a session store that declares durability but a checkpoint store that does not " +
            "(RunnerDeps.checkpointStore.durability): a durable park needs BOTH halves, so the conversation survives " +
            "the restart while the parked approval that was to resume it does not");
    }
    return undefined;
}
export function durableParkGapFor(deps, spec = {}) {
    const checkpointStore = resolveCheckpointStore(spec, deps);
    return durableParkGapOf({
        checkpointWired: checkpointStore !== undefined,
        checkpointDurable: declaresDurable(checkpointStore, "checkpointStore"),
        sessionDurable: declaresDurable(deps.sessionStore, "sessionStore"),
    });
}
function syntheticCheckpoint(scope) {
    return {
        token: mintCheckpointToken(),
        checkpointId: mintCheckpointId(),
        scope,
        sessionId: `${scope}:session`,
        leafId: `${scope}:leaf`,
        gate: { kind: "human", reason: "park wiring self-check (design/252 G-6) — no person is being asked", toolName: "SelfCheck" },
        pendingAction: {
            kind: "tool_approval",
            toolCallId: `${scope}:call`,
            toolName: "SelfCheck",
            args: { probe: true, nested: { depth: 2, list: [1, 2, 3] } },
            boundInputHash: boundInputHashOf({ probe: true, nested: { depth: 2, list: [1, 2, 3] } }),
            hasBidiControls: true,
            preview: { probe: true, note: "park wiring self-check display stub" },
            previewWithheld: "oversize",
            requiresRealApproval: true,
            mandated: true,
            denialLimitFallback: { consecutive: 3, total: 3, limit: "consecutive", autoDenyAfterMs: 0 },
            origin: "denial_limit_fallback",
            askClass: "denial_limit_fallback",
            classes: ["denial_limit_fallback"],
            batchToolCallIds: [`${scope}:call`],
            completedCallIds: [],
        },
        state: { activeTools: ["SelfCheck"], nestedStats: { tokens: 0, turns: 0, tasks: 0, costMicroUsd: 0, anyUnpriced: false } },
        status: "pending",
        createdAt: Date.now(),
        version: MAX_SUPPORTED_CHECKPOINT_VERSION,
        suspendCount: 1,
        suspendedAt: Date.now(),
        resourceLedger: { spentMicroUsd: 0, spentTokens: 0, spentTurns: 0, sliceCount: 1 },
        humanReview: { count: 1, totalWaitMs: 0, gates: [{ kind: "human", waitMs: 0, decision: "approve", toolName: "SelfCheck", toolCallId: `${scope}:selfcheck-call`, toolArg: "park self-check probe" }] },
        sourceTaskId: `${scope}:task`,
        principal: `${scope}:principal`,
        durableApproval: { scope, ttlMs: PARK_SELFCHECK_ROW_TTL_MS },
        deadline: Date.now() + PARK_SELFCHECK_ROW_TTL_MS,
    };
}
function faithfulnessDelta(sent, got) {
    const project = (cp) => ({
        token: cp.token,
        checkpointId: cp.checkpointId,
        scope: cp.scope,
        sessionId: cp.sessionId,
        leafId: cp.leafId,
        gate: cp.gate,
        pendingAction: cp.pendingAction,
        state: cp.state,
        deadline: cp.deadline,
        createdAt: cp.createdAt,
        version: cp.version,
        suspendCount: cp.suspendCount,
        suspendedAt: cp.suspendedAt,
        resourceLedger: cp.resourceLedger,
        humanReview: cp.humanReview,
        sourceTaskId: cp.sourceTaskId,
        principal: cp.principal,
        durableApproval: cp.durableApproval,
    });
    const a = canonicalize(project(sent));
    const b = canonicalize(project(got));
    return a === b ? undefined : `the row came back different from the row that was filed (sent ${a}; read ${b})`;
}
export async function probeParkRoundTrip(deps, spec = {}) {
    const gap = durableParkGapFor(deps, spec);
    const gapCell = gap !== undefined ? { durableTopologyGap: gap } : {};
    const store = resolveCheckpointStore(spec, deps);
    if (store === undefined) {
        return {
            verdict: "not_probed",
            findings: [],
            summary: "no checkpoint store is wired on this assembly — there is no park lane to probe (the manifest reports the same fact as parkLane.capable: false)",
            ...gapCell,
        };
    }
    const scope = `${PARK_SELFCHECK_SCOPE_PREFIX}${mintCheckpointToken()}`;
    const cp = syntheticCheckpoint(scope);
    const said = (err) => {
        try {
            const m = err instanceof Error ? err.message : undefined;
            return typeof m === "string" ? m : `a ${typeof err} the store threw`;
        }
        catch {
            return "a value the store threw that could not be described";
        }
    };
    const shown = (v) => {
        try {
            return typeof v === "string" ? JSON.stringify(v) : `a ${typeof v}`;
        }
        catch {
            return "an undescribable value";
        }
    };
    const fenceQuietly = async () => {
        await within(async () => {
            try {
                await store.expire(cp.token, scope);
            }
            catch {
            }
        }, "the cleanup fence");
    };
    const failed = async (code, detail) => {
        await fenceQuietly();
        return { verdict: "failed", findings: [{ code, detail }], scope, summary: `the park lane failed its round-trip self-check at "${code}": ${detail}`, ...gapCell };
    };
    let putStarted;
    const put = await within(() => {
        const p = Promise.resolve().then(() => store.put(cp.token, cp));
        putStarted = p;
        return p;
    }, "put");
    if ("timedOut" in put) {
        void putStarted?.catch(() => { }).then(() => store.expire(cp.token, scope)).catch(() => { });
        return await failed("put_failed", put.timedOut);
    }
    if ("threw" in put)
        return await failed("put_failed", `the checkpoint store refused to file a synthetic park: ${said(put.threw)}`);
    const first = await within(() => store.get(cp.token), "get");
    if ("timedOut" in first)
        return await failed("row_not_readable", first.timedOut);
    if ("threw" in first)
        return await failed("row_not_readable", `the checkpoint store threw reading back the row it had just accepted: ${said(first.threw)}`);
    const read = first.ok;
    if (read === null)
        return await failed("row_not_readable", "the checkpoint store accepted the row and then answered null for its own token — a park filed here would be unresumable");
    if (typeof read !== "object")
        return await failed("row_not_readable", `the checkpoint store answered ${read === undefined ? "undefined" : typeof read} for its own token — neither a checkpoint nor the absence of one`);
    let delta;
    let status;
    try {
        delta = faithfulnessDelta(cp, read);
        status = read.status;
    }
    catch (err) {
        return await failed("row_not_faithful", `the row the store returned could not be read for comparison: ${said(err)}`);
    }
    if (delta !== undefined)
        return await failed("row_not_faithful", delta);
    if (status !== "pending")
        return await failed("row_not_pending", `the filed row came back with status ${shown(status)} — a park in any other status is one nobody can resolve`);
    const enumerable = store.listByScope !== undefined;
    if (store.listByScope !== undefined) {
        const listByScope = store.listByScope.bind(store);
        const listed = await within(() => listByScope(scope), "listByScope");
        if ("timedOut" in listed)
            return await failed("row_not_enumerable", listed.timedOut);
        if ("threw" in listed)
            return await failed("row_not_enumerable", `listByScope threw for the probe's own scope: ${said(listed.threw)}`);
        let present;
        try {
            present = Array.isArray(listed.ok) && listed.ok.some((row) => row?.token === cp.token);
        }
        catch (err) {
            return await failed("row_not_enumerable", `the listByScope result could not be read: ${said(err)}`);
        }
        if (!present)
            return await failed("row_not_enumerable", `listByScope("${scope}") did not include the pending row it holds — an inbox enumerating this scope would show no approvals`);
    }
    const fence = await within(() => store.expire(cp.token, scope), "expire");
    if ("timedOut" in fence)
        return await failed("fence_failed", fence.timedOut);
    if ("threw" in fence)
        return await failed("fence_failed", `expire threw on the probe's own pending row: ${said(fence.threw)}`);
    const fenced = fence.ok === true;
    const second = await within(() => store.get(cp.token), "get (after the fence)");
    if ("timedOut" in second)
        return await failed("fence_not_durable", second.timedOut);
    if ("threw" in second)
        return await failed("fence_not_durable", `the store threw re-reading the fenced row: ${said(second.threw)}`);
    const after = second.ok;
    let afterStatus;
    if (after !== null) {
        if (typeof after !== "object")
            return await failed("fence_not_durable", `the store answered ${after === undefined ? "undefined" : typeof after} re-reading the fenced row — neither a checkpoint nor the absence of one`);
        try {
            afterStatus = after.status;
        }
        catch (err) {
            return await failed("fence_not_durable", `the fenced row's status could not be read: ${said(err)}`);
        }
        if (afterStatus !== "expired") {
            return await failed(fenced ? "fence_not_durable" : "fence_failed", fenced
                ? `expire reported a win and the row reads ${shown(afterStatus)} — the contract's transition is pending → expired, so the CAS did not land`
                : `expire lost an UNCONTENDED CAS and the row reads ${shown(afterStatus)} — the fence that keeps a checkpoint from being both reaped and resumed does not close here`);
        }
    }
    const steps = `filed, read back${enumerable ? ", enumerated" : ""} and fenced`;
    const notExercised = enumerable ? "" : " (this store implements no listByScope, so the inbox enumeration was NOT exercised)";
    const casNote = fenced ? "" : " (the expire CAS reported a loss while the row closed — consistent with store housekeeping, but a backend that mis-reports CAS wins is not distinguished here)";
    return {
        verdict: "round_trip_ok",
        findings: [],
        ...(fenced ? {} : { casLossObserved: true }),
        scope,
        summary: after === null
            ? `the park lane ${steps} a synthetic checkpoint${notExercised} — the row is no longer present (a deleting backend or its own housekeeping removed it), so nothing resumable remains${casNote}`
            : `the park lane ${steps} a synthetic checkpoint${notExercised} — residual expired row in scope "${scope}"${casNote}`,
        ...gapCell,
    };
}