from Hacker News

Incant – add magic spells to your code

by montyanderson on 6/15/25, 9:33 PM with 11 comments

• by thih9 on 6/18/25, 8:02 AM

  Note that this is a very simple library and not very efficient. E.g. for the code that filters an array, it would run N prompts[1]:

      `You are a filter agent.\nYour job is to return whether an item matches the criteria: ${criteria}\nRespond only with true or false.`
  

  It's a cool demo, but I wouldn't use that in production; IMO having that code in a separate library offers little benefit and increases the risk of misuse.

  [1]: https://github.com/montyanderson/incant/blob/73606e826d6e5b0...

• by voidUpdate on 6/18/25, 10:44 AM

  So this is just asking an LLM to filter or select from an array? Where do the magic spells come in?

• by helloplanets on 6/18/25, 6:42 AM

  How does this differ from function calling? For example, the basic enums example for Gemini function calling:

  > color_temp: { type: Type.STRING, enum: ['daylight', 'cool', 'warm'], description: 'Color temperature of the light fixture, which can be `daylight`, `cool` or `warm`.', }

  https://ai.google.dev/gemini-api/docs/function-calling?examp...

• by marcus_holmes on 6/18/25, 4:03 AM

  I'm curious how the hallucination-free guarantee works? Does it only guarantee that the output is a subset of the input?

  In the case of the male names, if I include a gender-neutral name like "Sam" does that include it because it is a male name, or exclude it because it is a female name? Can I set this to be inclusive or exclusive?

  Looks interesting, though. Nice work.

• by jollyllama on 6/18/25, 12:57 PM

  vibecoding is a hell of a drug

• by supermatt on 6/18/25, 6:48 AM

  > no hallucinations possible

  It can still hallucinate a response that is defined in the filter.

  E.g if you have a filter with names of capital cities [“London”, “Paris”, “Madrid”] , and you ask “What is the capital of France” it could respond “Madrid”