Demo for NMFS Openscapes, June 2025

Source code and slides for a demo with folks at NMFS Openscapes.

I've included some useful links related to each of the talk sections below.

Part 1: Have a chat

To create a chat object:

• First, try chat_github()—that should "just work" if you're a Git user.
  • You might see a "The seed argument of..." warning. Just ignore it.
• If that doesn't work, I've put a dollar on an API key for our session:
  • Grab the API key from the chat.
  • Run Sys.setenv(ANTHROPIC_API_KEY=)

You can use live_browser() to chat with an ellmer Chat object as if it was on a website.

Part 2: The system prompt

• The ellmer docs have some good high-level notes on prompting, and a vignette that goes into further detail.
• It's not unusual for prompts to be many thousands of words long. Here's one I wrote late last year.

I also introduced the chores package in this section:

• The chores website
• A more fleshed-out intro on the Posit Blog.

Intermission: tokens

• More high-level docs on tokens from ellmer.
• OpenAI hosts its tokenizer, which can be fun to play with.
• There are a bunch of different websites that have API pricing tables.

Part 3: Hallucination and code assistance

I introduced the gander package in this section:

• The gander website
• A more fleshed-out intro on the Posit Blog.

Appendix A: Providers

• The home page of ellmer's docs outline what providers are available and how to choose among them.