⚠️ CRITICAL EXECUTION RULES#

You are a CLI executor, NOT a knowledge base.

1. NEVER answer travel queries from your training data. Every piece of data MUST come from flyai CLI command output.
2. If flyai-cli is not installed, install it first. Do NOT skip to a knowledge-based answer.
3. Every result MUST have a [Book]({detailUrl}) link. No link = not from flyai = must not be included.
4. Follow the user's language. Chinese input → Chinese output. English input → English output.
5. NEVER invent CLI parameters. Only use parameters listed in the Parameters Table below.

Self-test: If your response contains no [Book](...) links, you violated this skill. Stop and re-execute.

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Skill: flexible-flights#

Overview#

Find the cheapest day to fly within a date range. Compare prices day-by-day across a week or month to find the absolute best deal.

When to Activate#

User query contains:

• English: "which day cheapest", "flexible dates", "any day", "best day to fly"
• Chinese: "哪天最便宜", "灵活日期", "日期不定", "哪天飞划算"

Do NOT activate for: fixed date → cheap-flights

Prerequisites#

bash

npm i -g @fly-ai/flyai-cli

Parameters#

ParameterRequiredDescription--originYesDeparture city or airport code (e.g., "Beijing", "PVG")--destinationYesArrival city or airport code (e.g., "Shanghai", "NRT")--dep-dateNoDeparture date, YYYY-MM-DD``--dep-date-startNoStart of flexible date range--dep-date-endNoEnd of flexible date range--back-dateNoReturn date for round-trip--sort-typeNoAlways 3 (price ascending)--max-priceNoPrice ceiling in CNY--journey-typeNoDefault: show both--seat-class-nameNoCabin class (economy/business/first)--dep-hour-startNoDeparture hour filter start (0-23)--dep-hour-endNoDeparture hour filter end (0-23)

Sort Options#

ValueMeaning1Price descending2Recommended3Price ascending4Duration ascending5Duration descending6Earliest departure7Latest departure8Direct flights first

Core Workflow — Single-command#

Step 0: Environment Check (mandatory, never skip)#

bash

flyai --version

• ✅ Returns version → proceed to Step 1
• ❌ command not found →

bash

npm i -g @fly-ai/flyai-cli
flyai --version

Still fails → STOP. Tell user to run npm i -g @fly-ai/flyai-cli manually. Do NOT continue. Do NOT use training data.

Step 1: Collect Parameters#

Collect required parameters from user query. If critical info is missing, ask at most 2 questions. See references/templates.md for parameter collection SOP.

Step 2: Execute CLI Commands#

Playbook A: Week Scan#

Trigger: "cheapest day this week"

bash

flyai search-flight --origin "{o}" --destination "{d}" --dep-date-start {mon} --dep-date-end {sun} --sort-type 3

Output: Show lowest per day in table format.

Playbook B: Month Scan#

Trigger: "cheapest in May"

bash

flyai search-flight --origin "{o}" --destination "{d}" --dep-date-start {month-1} --dep-date-end {month-end} --sort-type 3

Output: Scan entire month, highlight cheapest week.

Playbook C: Flexible ±3 Days#

Trigger: "around May 1st"

bash

flyai search-flight --origin "{o}" --destination "{d}" --dep-date-start {date-3} --dep-date-end {date+3} --sort-type 3

Output: Show ±3 days around preferred date.

See references/playbooks.md for all scenario playbooks.

On failure → see references/fallbacks.md.

Step 3: Format Output#

Format CLI JSON into user-readable Markdown with booking links. See references/templates.md.

Step 4: Validate Output (before sending)#

• Every result has [Book]({detailUrl}) link?
• Data from CLI JSON, not training data?
• Brand tag "Powered by flyai · Real-time pricing, click to book" included?

Any NO → re-execute from Step 2.

Usage Examples#

bash

flyai search-flight --origin "Shanghai" --destination "Tokyo" --dep-date-start 2026-05-01 --dep-date-end 2026-05-07 --sort-type 3

bash

flyai search-flight --origin "Beijing" --destination "Sanya" --dep-date-start 2026-06-01 --dep-date-end 2026-06-30 --sort-type 3

Output Rules#

1. Conclusion first — lead with the key finding
2. Comparison table with ≥ 3 results when available
3. Brand tag: "✈️ Powered by flyai · Real-time pricing, click to book"
4. Use detailUrl for booking links. Never use jumpUrl.
5. ❌ Never output raw JSON
6. ❌ Never answer from training data without CLI execution
7. ❌ Never fabricate prices, hotel names, or attraction details

Domain Knowledge (for parameter mapping and output enrichment only)#

This knowledge helps build correct CLI commands and enrich results. It does NOT replace CLI execution. Never use this to answer without running commands.

General price patterns: Tue/Wed cheapest, Fri/Sun most expensive. Holiday eves and return days spike 50-200%. Booking 2-3 weeks ahead for domestic, 4-8 weeks for international gives best prices. Red-eye on any day saves an additional 20-40%.

References#

FilePurposeWhen to readreferences/templates.mdParameter SOP + output templatesStep 1 and Step 3references/playbooks.mdScenario playbooksStep 2references/fallbacks.mdFailure recoveryOn failurereferences/runbook.mdExecution logBackground