OpenBook — Real-time Signals for Places & Businesses

What is OpenBook?

OpenBook is an open, non-commercial platform that records real-world changes as structured data.
The core data type is a Signal — a lightweight, time-stamped observation:

• - "Seesaw on Yuyuan Road raised their Americano to 32 yuan"
• "The bakery next to Changning Finance Park closed down"
• "New barista at BW Coffee makes great cold brew"

Signals are the changelog of the physical world. One accurate Signal is worth more than a hundred opinions.

Setup

OpenBook is a public, open platform — no API keys, tokens, or credentials are required. All data is publicly accessible and contributions are welcome from anyone.

• - Reading data: No authentication needed. Use the public API or browse the website.
• Publishing data: Signals are submitted via the OpenBook website or as GitHub Pull Requests. An automated review checks format and content quality before merging.

When to Suggest Creating a Signal

When the user mentions something that could be a useful Signal, ask the user if they would like to share it on OpenBook. Good candidates include:

• - A change: price increase, new menu, renovation, staff change
• A closure or opening: shop closed, new store opened
• A recommendation or warning: great new dish, found a bug in food
• A quick observation: crowded this weekend, beautiful cherry blossoms today

Important: Always get the user's explicit consent before publishing. For example: "That's a useful observation! Would you like me to share it as a Signal on OpenBook so others can benefit?"

Signal Fields

Field	Required	Description
targetname	Yes	Name of the place or business
targetcategory

Yes | food, housing, shopping, transport, service, general | | city | Yes | City name (e.g., Shanghai, New York, Tokyo) | | signaltype | Yes | update, pricechange, closure, newopening, qualitychange, warning, recommendation, event | | content | Yes | What happened — concise and factual | | severity | Yes | info, notable, important, critical | | date | Yes | ISO timestamp (YYYY-MM-DDTHH:mm:ss+08:00) | | neighborhood | No | Street or area (e.g., 愚园路, East Village) | | district | No | Administrative district (e.g., 长宁区, Manhattan) | | tags | No | Descriptive keywords | | suitable_for | No | Audience: backpacker, family, kids, pets, couple, solo, business, vegetarian, halal, accessible, elderly | | price | No | Price amount if mentioned | | price_unit | No | Currency (default: CNY) | | subcategory | No | Specific type (e.g., coffee, ramen, hotpot) |

How to Publish a Signal

After the user confirms they want to publish, direct them to the Signal submission page. The website accepts natural language input and uses AI to extract structured fields automatically.

Website URL: https://openbook.now/signal

Alternatively, Signals can be submitted as Pull Requests to the GitHub repository at https://github.com/josephliver623/OpenBook in the data/signals/ directory using Markdown files with YAML frontmatter.

How to Query Signals

Via Web API

OpenBook provides a public read-only API. No authentication required.

Base URL: https://openbook.now

Query Signals:

GET /api/trpc/signals.query?input={"0":{"json":{"city":"Shanghai","category":"food","limit":10}}}

Available filters: city, category, target, signaltype, suitablefor, limit

Get Signal Detail:

GET /api/trpc/signals.detail?input={"0":{"json":{"id":"signal-id-here"}}}

API Documentation:

GET /api/trpc/signals.docs

Via the Explore Page

Users can browse all Signals on the Timeline view: https://openbook.now/explore

Auto-Enrichment

When helping the user create a Signal, use your knowledge to suggest missing fields:

• - "愚园路" → city: Shanghai, district: 长宁区 or 静安区
• "东村" → city: New York, district: Manhattan, neighborhood: East Village
• A restaurant name → targetcategory: food, appropriate subcategory
• Price mentioned → extract price and priceunit

Always show the enriched fields to the user for confirmation before submitting.

Presenting Signals

When showing Signals to users, use a compact timeline format:

Recent changes at 老成都:

Mar 14 | Price change
Lunch set meal went from ¥38 to ¥45

Mar 10 | Quality change
New chef, quality has dropped

Feb 28 | Recommendation
Boiled fish is still the signature dish, generous portions

About OpenBook

OpenBook is open-source, non-commercial, and designed for both humans and AI Agents.
Every Signal helps travelers, locals, and AI assistants make better decisions.

• - Website: https://openbook.now
• GitHub: https://github.com/josephliver623/OpenBook
• License: MIT