Hacker News Keyword Watch

Daily scan of the Hacker News front page. Fires a literal contains arm for exact keyword mentions, then falls back to an AI-arm that catches fuzzy topic matches the literal arm would miss.

What it does

On each fire, the monitor pulls the top stories via the hacker-news-top tool. The when: block has three arms evaluated in order:

1. Literal keyword match — {{check.summary}} contains InTouch. Fast, deterministic, free.
2. AI-arm fuzzy match — only reached when the literal arm didn't match. Sends the digest to the AI assistant with a precise prompt asking whether any story is about AI workflow automation / agents / LLM orchestration. Catches posts that describe the topic without using your exact keywords.
3. Else — no match anywhere; do nothing.

Only one arm fires per evaluation (first match wins). The AI-arm pays one LLM call per fire whenever the literal arm misses — design your schedule cadence accordingly (hourly = 24 calls/day; daily = 1 call/day).

Edit before installing

In monitor.yaml:

• Replace InTouch in the literal arm with your exact brand/topic name.
• Edit the AI-arm prompt to describe the fuzzy topic you want to detect. Be specific about what counts AND what doesn't ("be conservative; do not match generic AI news"). Vague prompts trigger false positives.
• For multiple literal keywords, chain with ||: {{check.summary}} contains InTouch || {{check.summary}} contains Blue Isle

Bindings used

• {{check.summary}} — formatted digest of top stories (titles + URLs + scores).
• {{check.stories}} — raw stories as a JSON array.
• {{check.count}} — number of stories returned.
• {{ai_reasoning}} — set by the AI-arm; explains why it matched (only available inside the AI-arm's do: actions).

Tool used

hacker-news-top — hub-installed YAML tool, no API key required.

Pattern showcase

The literal-then-AI pattern is the classic "cheap match first, smart match when needed" optimization. Use it whenever:

• The cheap arm handles the obvious 90% (saves LLM tokens).
• The AI arm catches the long tail of paraphrased / loosely-related matches the literal would miss.

Requires the AI assistant to be configured (Server Settings → AI Assistant). If no AI is configured, the AI-arm returns false safely (no false-fire), and the monitor effectively becomes a literal-only watch.