Symphony.run

Symphony.run is a chatbot builder tool that writes programs you can talk to, powered by conversational functions. Symphony is a developer tool for building conversational programs: you write TypeScript or Python functions, and a natural language layer routes user requests to the right functions at runtime, so users can state goals in plain language instead of clicking through fixed flows.

Symphony is a development tool built around a single proposition: programs should be something you can talk to. Rather than assembling a rigid menu of buttons or a fixed conversational flow, developers write functions (the homepage shows examples such as search_contacts.ts, get_events.ts, search_places.py and suggest_event.ts) and the system decides which of them to call based on what the user says. The result is a natural language interface layered over real code and real data, with the model handling intent and orchestration while the underlying functions do the actual work. The homepage example captures the intended experience. A request like getting drinks with Dan tomorrow evening after studio is expressed casually, in a single sentence, yet it depends on several capabilities at once: looking up a contact, checking a calendar, finding a place, and proposing an event. In Symphony, those capabilities exist as discrete typed functions in the languages a developer already writes, and the conversational layer stitches them together at runtime. Instead of predicting every possible user journey in advance, the developer exposes tools and lets the conversation route between them. This places Symphony in the emerging class of tool-calling and agent orchestration frameworks, but with an emphasis on the conversational program as the product rather than a library you bolt on. It suits developers and product teams building assistants, scheduling experiences, contact search, or any interface where users state goals in their own words and expect the software to figure out the steps. Teams weighing it against general purpose agent frameworks should note that Symphony is opinionated about functions as the unit of capability. The practical draw is that the code stays ordinary. Functions live in TypeScript and Python files, which keeps logic testable and versioned like any other part of the repository, while the conversational layer handles routing. The project is open source, with a repository and a Discord community linked from the site, and documentation and a blog cover the setup path. The homepage is deliberately minimal and does not publish pricing tiers, so buyers should confirm commercial terms before committing production workloads.