03-smart-search-fallback.md

Smart fallback when search returns no results

Source: 用户增长-使用者体验改进清单.md item #3

Problem

When search_knowledge.py finds no matching results, it shows a generic "Not found" message and suggests adding a new lesson. A user who just tried their first search is likely to leave at this point.

Suggested implementation

Replace the current no-results output with tiered suggestions:

1. Domain suggestions — if the query resembles a known domain tag, suggest narrowing by domain
2. Broad mode hint — suggest --broad or --ref as alternatives
3. Quick contribution link — point to the quick lesson template
4. Existing domain list — show top domains as examples

Example output:

❌ No exact match for 'docker network debug'

Suggestions:
  • Try domain filter: --lessons docker
  • Try broader search: --broad
  • Browse domains: docker / network / python / cloudflare
  • Quick contribution: scripts/quick-lesson.sh

Acceptance criteria

• No-result output offers actionable next steps
• Suggestions are computed from actual available domains/lessons
• Output still fits in terminal, not too verbose
• Existing --suggest mode still works independently