LLM persona via --append-system-prompt

Inject style/role/safety rules at the system level — keeps your user prompt focused on the data, not on persona-prefixing.

$ curl -s -A "oneliner101/1.0" \
     "https://www.reddit.com/r/singularity/top.json?limit=15&t=week" \
  | jq -r '.data.children[].data | "[\(.score)] \(.title)"' \
  | claude -p \
      --append-system-prompt "You are a senior analyst at trends101. You reject hype. Cite specific titles. Output ≤120 words." \
      "Weekly r/singularity pulse."

1. [01] curlcurl … reddit.com/r/singularity/top.json?…&t=week
   Reddit JSON, weekly window.
2. [02] jqjq -r '.data.children[].data | "[\(.score)] \(.title)"'
   Compact `[score] title` lines.
3. [03] claude--append-system-prompt "You are a senior analyst …"
   Adds to the default system prompt without replacing it. Use this 90% of the time. `--system-prompt` replaces entirely (risky — loses claude's safety defaults).
4. [04] claude"Weekly r/singularity pulse."
   User prompt stays minimal — just states the task. Persona/style/length rules live in the system prompt, not muddled into the user message.

Three threads dominate: (1) the M5 Pro benchmarks are getting heat for cherry-picked workloads — "M5 Pro vs H100" is anchored at score 612 but has 230 dissenting comments. (2) The agentic-RAG vs vanilla-RAG debate spilled out of r/MachineLearning, with "Vector search is dead" at 481. (3) Quiet enthusiasm for local-first ML — "Llama 4 on a $400 mini-PC" at 312 is the most-saved post of the week. Skepticism rising overall.

• Use `--append-system-prompt-file ./prompts/persona.md` for longer system prompts.
• System-prompt content is cached server-side (better hit rate on repeated runs with same persona).