Public spec library
The agent does not run on opacity.
Architecture, security, concepts, and the vision behind YiG — written as durable articles you can forward to your security reviewer, your compliance officer, or the controller next desk over.
User manuals
Free downloadable setup and usage guides for the Yigcore Excel Add-in public beta.
Vision
Why YiG exists, and what kind of product we are building.
- Yig product line 2026-05-13 A guided tour of the Yig suite — Thinker, Enterprise, Finance, and the Office Add-ins — and which one fits which team.
- Computer as instrument, not lifestyle product 2026-05-10 Why Yig looks more like Bloomberg than Notion, and what that means for finance teams.
- The close is not a process 2026-05-11 Why month-end close is a judgment-intensive reckoning, not a task list, and what that means for the software that touches it.
- Against the co-pilot metaphor 2026-05-11 The co-pilot frame is ubiquitous in enterprise AI. It is the wrong frame for finance. The metaphor you choose determines the product you build.
Concepts
How to think about YiG — the patterns and principles that govern every workflow.
- You drive. Yig drafts. — A HITL design principle 2026-05-10 Human-in-the-loop is not a feature. It is the architecture.
- Why the spreadsheet is still winning 2026-05-11 Finance teams keep their workbooks not because they have not found a better tool, but because the workbook is the right primitive. What that demands of agents.
- The yellow flag 2026-05-11 Why designing AI uncertainty as a first-class product feature is the correct architectural choice — not a limitation to hide.
- How the reviewer gate works 2026-05-11 The architectural component that enforces human-in-the-loop. What it enforces, how it is built, and why it cannot be bypassed by configuration.
- Workflow templates explained 2026-05-11 What a workflow template is, how the planner executes it, how templates handle edge cases, and how to read the output shape.
- The BYOK model 2026-05-11 What bring-your-own-key means for data handling, compliance, and model selection. Why Yig is not in the inference business.
- Run your first GL reconciliation 2026-05-11 A walkthrough of the GL reconciliation workflow from first invocation to approved output — what happens at each layer and what the reviewer sees.
- Connecting Yig Thinker to Slack 2026-05-11 How the Slack surface works: webhook setup, thread-based review flow, what the reviewer sees, and what gets logged.
- The surface contract 2026-05-16 Slack, Teams, Feishu, and Excel are not integration targets. They are the surface where work happens, and that changes what the agent owes them and what they owe the agent.
- What we don't cache and why 2026-05-16 Agent state is a trust decision before it is a performance decision. Yig rebuilds what should be auditable and persists only what survives review.
Architecture
How YiG is structured. Trust boundaries, layers, and what crosses each boundary.
- Architecture overview 2026-05-10 Four layers, clear trust boundaries, and what crosses each boundary. No internals.
- What the operator controls 2026-05-11 The full operator control surface: surfaces, workflows, model, reviewers, audit destination, and deployment topology. What is configurable and what is not.
- Deployment topologies in practice 2026-05-11 Local, customer cloud, and single-tenant managed — the tradeoffs between each topology, when to choose each, and how to migrate between them.
Security
Data residency, audit log, reviewer gate, and what we will not do.
- Security and data handling 2026-05-10 Where customer data lives, what we log, and what we will never do.
- Reading an audit log 2026-05-11 What each field in a Yig audit record means, how records chain together into a run trail, and how to use the trail in a downstream audit.
- The shape of an audit trail 2026-05-16 An audit trail is not a log file. It is a reconstruction contract: from the recorded state, a stranger can rebuild the decision that put the system here. Most observability is not auditable.
Specs
Public summaries of completed internal specifications.