@sema-agent/core/dist/core/memory-engine/scan.js

Stateless, task-oriented AI agent core

import { detectSecret, MEMORY_WRAPPER_TAGS } from "../memory.js";
import { defuseFenceMarkers, sanitizeUntrustedText } from "../untrusted-text.js";
export const MEMORY_FILENAME_SEGMENT_RE = /^[A-Za-z0-9._-]+$/;
export function scanMemoryFileName(relPath) {
    for (const segment of relPath.split("/")) {
        if (segment === "")
            continue;
        if (!MEMORY_FILENAME_SEGMENT_RE.test(segment)) {
            return {
                code: "filename",
                reason: `file name contains characters outside the memory whitelist (allowed: letters, digits, ".", "_", "-" per path segment)`,
            };
        }
    }
    return undefined;
}
export function scanMemoryWrite(text, opts = {}) {
    const findings = [];
    if (opts.maxBytes !== undefined) {
        const size = Buffer.byteLength(text, "utf8");
        if (size > opts.maxBytes) {
            findings.push({ code: "too_large", reason: `${size} bytes — over the ${opts.maxBytes}-byte cap; split or trim it (rejected, NOT truncated)` });
        }
    }
    const secretLabel = detectSecret(text);
    if (secretLabel !== null) {
        findings.push({ code: "secret", reason: `detected ${secretLabel}` });
    }
    if (sanitizeUntrustedText(text, [...MEMORY_WRAPPER_TAGS]) !== text) {
        findings.push({ code: "injection", reason: "contains a framing break-out tag (<system-reminder>/<user_memory> family)" });
    }
    else if (/^[ \t]*(?:<{3,}|>{3,})/m.test(text) && defuseFenceMarkers(text) !== text) {
        findings.push({ code: "injection", reason: "contains an untrusted-fence sentinel at line start (a run of 3+ '<' or '>')" });
    }
    return findings;
}
export function scanRemediation(code) {
    switch (code) {
        case "secret":
            return "Remove the secret value — store a POINTER to where it lives (env var name, vault path) instead of the value itself.";
        case "injection":
            return "Remove the markup: memory files must not contain <system-reminder>/<user_memory> tags or runs of 3+ '<'/'>' (they would forge the injection framing when this memory is loaded).";
        case "filename":
            return 'Rename the file using only letters, digits, ".", "_" and "-" in each path segment.';
        case "too_large":
            return "Split the content into smaller topic files, or trim it.";
    }
}