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Verify is available to the closed beta cohort. These tools may move out of the core MCP. Join the waitlist at subtext.fullstory.com.
Verify is the verification layer built on top of core Subtext. While the main Docs tab covers session review — replaying user sessions, attaching comments, and inspecting events — Verify adds the tooling your agent needs to actively drive a browser, produce evidence, and leave a permanent record of its work. Everything here is beta: the APIs are stable enough to build on, but the shape of this stack may change as it moves toward general availability.

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What Verify adds

Core session review lives in the main Docs tab. Verify extends that foundation with six new capability areas.

Live Browser

A cloud-hosted browser your agent opens and controls. Every snapshot is enriched by Sightmap — semantic component names, source paths, visibility, and interactivity are surfaced automatically. Includes network and console inspection, device emulation, and the full interaction surface: click, fill, drag, upload, keypress, and more.

Artifacts

Upload screenshots and documents to cloud storage with artifact-upload, then generate fresh signed URLs with artifact-url. Artifacts give you a durable, shareable pointer to any piece of visual or documentary evidence your agent produces.

Proof Docs

Permanent, evidence-backed records of agent work. Open a doc with doc-create, attach before/after screenshots, diffs, and logs with doc-attach, then seal it with doc-close. The result is a versioned document you can read, diff, and share — a full audit trail for every change your agent makes.

Skills

Verify-specific slash commands that give your agent curated guidance without manual prompting. /subtext:proof drives the inner loop for capturing BEFORE/AFTER evidence. /subtext:live, /subtext:sightmap, /subtext:tunnel, /subtext:docs, and /subtext:comments each load the relevant tool catalog and usage patterns atomically.

Sightmap

The same Sightmap you define for session review enriches every Live Browser snapshot. YAML files in .sightmap/ map CSS selectors to semantic component names, source paths, and memory entries — contextual notes that appear as a [Guide] block at the top of every snapshot so your agent understands the UI without reading source.

Tunnel

The cloud-hosted browser cannot reach your machine directly. The Subtext Tunnel bridges it to your localhost dev server through a reverse tunnel — a lightweight local MCP server you add to your config alongside the main Subtext server.

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Skills reference

The Verify slash commands load focused, atomic guidance into your agent’s context on demand.
Core session review tools — review-open, comment-*, event-*, and the rest of the session inspection surface — are documented in the main Docs tab, not here.