Build a phase-gated EOL checklist sized to the sunset, with a named owner on every item. Use when the decision to retire is made and you need the operational plan.
Build a phase-gated EOL checklist sized to the sunset, with a named owner on every item. Use when the decision to retire is made and you need the operational plan.
intent
Generate a phase-gated EOL checklist tailored to the complexity of the sunset. Covers up to 15 functional areas across the lifecycle gates, but right-sizes the output so a minor feature deprecation gets a short punch list while a flagship product retirement gets the full cross-functional playbook. Every item names a verb and an owner.
type
component
theme
eol-transition
best_for
["Turning a sunset decision into an operational plan with owners and dates","Making sure a retirement doesn't strand data, contracts, or inventory","Right-sizing process so a feature deprecation doesn't get a flagship playbook"]
scenarios
["We've decided to retire the legacy module in December — what actually has to happen between now and then?","Hardware line with channel partners and service contracts; I need the full cross-functional checklist"]
estimated_time
20-40 min
EOL Checklist
Purpose
Turn a sunset decision into a phase-gated operational plan: what must happen, in which lifecycle
phase, and who owns it. The output is a working checklist — sticky-note-sized items, each with a
verb and a named function — not a strategy document.
The checklist is sized to the sunset. A deprecated internal tool gets a dozen items across
three phases. A regulated hardware line gets a cross-functional playbook across six phases with
gate criteria between them. Both are correct; using the wrong one is the failure.
Input
Works best with: The product being sunset and any dates you're already committed to.
Also useful: Customer and revenue scale, whether a replacement exists and how ready it is,
contract or regulatory obligations, and whether hardware, inventory, or channel partners are in
play.
Anything supplied with the invocation itself — text after the skill name, a pasted context dump, or
an appended ARGUMENTS: line — counts as answers already given. Use it and skip whatever it
covers; don't re-ask.
Arriving empty-handed? That works too. The skill asks up to three questions — what's being
sunset and at what scale, whether there's a replacement, and what hard deadlines exist — then picks
a level and builds. Unknowns become labeled assumptions rather than blockers.
Example invocations:
EOL checklist for our legacy reporting module, shutting down Dec 31, ~400 accounts.
Build the heavy checklist for a hardware retirement — service contracts, 8 resellers, UL certified.
Key Concepts
Right-Size Before You Build
Not all EOLs play out the same. Most land in the middle. Pick the level deliberately:
Level 1 — Light
Level 2 — Standard
Level 3 — Heavy
Typical scope
Feature, internal tool, unversioned API
Commercial product, active customers
Revenue-critical, hardware, regulated
Phases used
2-3 (NSC, EOS, EOL)
4-5 (NSC, EOS, EOE, EOM, EOL)
All 6 (NSC through EOSRV)
Functional areas
4
11
15
Gate criteria
Not needed
Between major phases
Between every phase, with approvers
Output feel
Punch list
Working checklist with owners and dates
Cross-functional playbook
Level 2 is the default. Recommend a level, say why in one line, and let the user move it. If
they go lighter, name the specific area that drops out so the choice is informed. Never default
to Level 3 — a heavy checklist applied to a light sunset teaches teams that EOL process is
ceremony, and they'll skip it next time when it matters.
The level is yours to change mid-build. "Actually make this heavier" is a normal thing to hear
after the Legal row surfaces something.
The Lifecycle Gates
GA (General Availability): Actively sold and fully supported
NSC (Notice of Status Change): The decision is communicated; planning begins
EOS (End of Sale): No new customers can purchase
EOE (End of Expansion): Existing customers cannot add capacity or seats
EOR (End of Renewal): Existing contracts will not be renewed
EOM (End of Maintenance): Bug fixes and patches stop
EOL (End of Life): The product is retired
EOSRV (End of Service): All support and service obligations end
Which of these become checklist phases: GA is a state, not a phase of work — nothing is
checklisted there. EOR is contract-driven and only appears when renewals are in play. So working
checklists usually span the six actionable phases: NSC, EOS, EOE, EOM, EOL, EOSRV, with EOR
inserted when subscription or service contracts run past EOS.
Naming the gates you're not using is as useful as naming the ones you are. A Level 1 checklist
should say "EOE and EOSRV don't apply — nothing to expand, nothing to service."
The Fifteen Functional Areas
Filtered by level. The parenthetical marks the lowest level where each appears:
Area
Level
Product and Strategy
1
Engineering and Technical
1
Support
1
Documentation and Training
1
Legal and Contractual
2
Financial Planning
2
Sales
2
Marketing
2
Customer Success
2
IT Systems
2
Data Management
2
Inventory and Supply Chain
3
Channel and Partner Management
3
Regulatory and Compliance
3
Internal Organizational Alignment
3
The Sticky-Note Rule
Every item is 4 to 8 words, names a verb, and carries a named owner (a function, not a
person's calendar). "Legal reviews contracts" is an item. "Ensure appropriate review of all
relevant contractual obligations across the customer base" is a paragraph wearing a checkbox.
Why the owner is mandatory: an unowned item is a wish. Forcing a function onto every line
surfaces cross-functional gaps early — when you can't name who owns "notify channel partners," you
have just discovered that nobody does.
Phase Gates Are Commitments, Not Dates
A phase gate is what must be true before you advance, with an approver. "EOS to EOE: last-time-buy
orders closed — Approver: Sales VP." This is what stops an EOL from being one announcement followed
six months later by somebody quietly pulling a plug.
Anti-Patterns (what this is NOT)
Not a project plan. No Gantt, no dependencies graph, no resource loading.
Not exhaustive by default. Coverage proportional to risk, not maximum ceremony.
Not the decision. If the sunset itself is still in question, this is premature.
Not a substitute for the conversations. A checklist item saying "align with Legal" is not
alignment with Legal.
Application
Step 1: Set the level
Recommend from blast radius — customers, revenue, contracts, hardware, partners — then present all
three and let the user choose. If the level is genuinely unclear, ask:
"How complex is this sunset?
Light — a feature, internal tool, or unversioned API. Few users, all reachable.
Standard — a commercial product with paying customers and contracts.
Heavy — revenue-critical, hardware in the field, channel partners, or regulated.
Most sunsets are Standard. Which sounds like yours?"
Step 2: Select phases in scope
Map the level to phases, then check for the two overrides:
Contracts running past EOS? Insert EOR.
No service obligations at all? Drop EOSRV and say so.
If a date is genuinely unknown, write TBD — and if a date shouldn't be set yet (no migration
path exists), write Not scheduled and add an item naming the precondition. An invented EOL date
is a promise you will break in public.
Step 3: Build items per phase, per area
For each phase in scope, walk the functional areas warranted by the level. Each item:
Starts with a verb
Is 4 to 8 words
Names an owning function
Belongs to exactly one phase — the phase where the work happens, not where it's announced
Cover, at minimum, the four things sunsets most often strand:
Data — export format, availability window, deletion schedule
Contracts — renewal language, SLA terms, refunds or credits owed
Access — API keys, integrations, SSO, downstream systems that read from it
Money — forecast adjustment, revenue recognition, cost of the sunset itself
Step 4: Write gate criteria (Level 2+)
For each phase transition, list what must be true and who signs. Three to five criteria per gate is
plenty. If you can't name an approver, the gate isn't real.
Step 5: Post-EOL actions and assumptions
Always include a short post-EOL block — archival, final report, and a lessons-learned review.
The review is the item teams cut first and regret most; the next sunset is always easier when
someone wrote down what surprised you in this one.
Close with assumptions to validate — every unknown from Step 1, stated plainly.
Final Step: Offer what comes next
"Where next?
Map the stakeholder conversations — who to talk to, in what order (Recommended)
Build the internal enablement pack — support FAQ, sales talking points, objections
Convert this to a dated timeline — calendar dates against each phase
Reply with a number, a combination ('1 & 3'), or your own path."
Examples
examples/sample.md — Fieldlight Classic Dispatch (SaaS, Level 2, five phases)
examples/sample-industrial.md — NFA-200 controller line (industrial, Level 3, six phases with
a deliberately undated EOL)
Common Pitfalls
Pitfall 1: Ceremony Inflation
Symptom: Every sunset gets the 15-area, six-phase playbook because it's "more thorough."
Consequence: Teams learn EOL process is theater, skip it entirely on the next one — and the
next one is the one with the contracts.
Fix: Right-size deliberately. A Level 1 checklist that gets used beats a Level 3 that gets
ignored.
Pitfall 2: Unowned Items
Symptom: "Ensure customer data is exported." Owner: blank, or "the team."
Consequence: Everyone assumes someone else has it. On shutdown day, nobody did.
Fix: Every item names a function. If you can't name one, that's the finding — escalate it
rather than papering over it.
Pitfall 3: The Invented Date
Symptom: An EOL date gets written down because the checklist template had a blank for it.
Consequence: You announce a date, discover the migration path doesn't exist, and move it.
Customers who planned around the first date stop believing the second.
Fix:Not scheduled is a legitimate entry. Pair it with the precondition that would let you
schedule it.
Pitfall 4: Phase Collapse
Symptom: Everything lands in one phase called "EOL."
Consequence: You stop sales, stop support, and shut down on the same day. Customers experience
it as an outage with advance notice.
Fix: Separate the gates. Stopping sales is cheap and early; stopping service is expensive and
last.
Pitfall 5: Forgetting the Downstream Readers
Symptom: The checklist covers the product and its customers, but not the four internal systems
that quietly query its API.
Consequence: The product retires on schedule and three dashboards, a billing job, and a partner
integration break the next morning.
Fix: The IT Systems and Data Management areas exist for this. At Level 1, still ask once: what
reads from this?
References
Related Skills
These stand on their own — none is a prerequisite for this skill, and this skill isn't a
prerequisite for them. If you already picked a level elsewhere, just say "Level 2" and this skill
will build to it; there's no handoff artifact to carry.
eol-readiness-advisor — if the decision itself still needs
a case, or you want the level recommended for you
