Deck Analysis
The Deck Analysis page (/deck-analysis) guides you through a 5-step workflow. Step 2 generates the analysis prompt, Step 3 parses and renders the returned deck_profile JSON, Step 4 optionally generates a set-upgrade prompt using that parsed profile, and Step 5 parses and renders the returned set_upgrade_report JSON.
Workflow layout modes
Three layouts are available via the toolbar: Guided, Focused, and Expert. They present the same underlying steps with different amounts of context and guidance text.
Step 1 — Deck Setup
Choose an Input method (paste text or public deck URL) and provide either a Moxfield / Archidekt deck URL or pasted deck export text. The chosen mode round-trips with the form so it survives refreshes and step navigation. The service:
- Falls back to treating leading quantity-1 entries as the commander when no Commander section header is present (Moxfield plain-text exports), then validates the inferred commander against Scryfall before continuing.
- Rejects inferred commanders that are not legal by the workflow rules: legendary creature, legendary Vehicle, or a planeswalker whose oracle text says it can be your commander.
Step 2 — Analysis
Configure the analysis:
| Setting | Purpose |
|---|---|
| Target Commander Bracket | Bracket 1–5. Your AI uses this when evaluating card quality, interaction density, and upgrade suggestions. |
| Analysis questions | Select one or more questions from the buckets below. |
| Card name | Required when card-specific questions are selected. |
| Budget amount | Required when the budget-upgrade question is selected. |
| Decklist export format | Moxfield or Archidekt — required when category questions are selected; optional for versioning questions. |
| Include card versions | When checked, the original deck's set code and collector number are sent so your AI can preserve the exact printing for retained cards. |
| Preferred category names | Shown when Update categories is selected. One name per line; your AI will prefer these over inventing new ones. |
| Protected cards | Cards that must appear in every generated deck version. |
Click Generate Analysis Packet to build the reference data and analysis prompt. The generated prompt uses ## section headings (TASK, EVIDENCE RULES, BRACKET GUIDANCE, ANALYSIS QUESTIONS, OUTPUT FORMAT, REFERENCE DATA, DECKLIST) to keep long prompts structured.
The REFERENCE DATA block lists every deck card with its mana cost, type, and Oracle text. If the site operator has enabled the reference recency gate, Oracle text is condensed to mana cost and type for cards older than a year — these are already well known to the AI — while recent cards keep their full text. This trims prompt length without changing the analysis; by default the full Oracle text is included for every card.
Step 3 — Analysis Results
Paste the fenced deck_profile JSON block or raw JSON payload returned from your AI. You can also paste a saved deck_profile JSON file here directly without filling out Steps 1 and 2 again. The page validates the payload, parses it into a strongly typed model, and renders a readable summary of:
- Format and commander
- Game plan, speed, primary axes, and synergy tags
- Strengths, weaknesses, deck needs, and weak slots
- Per-question answers with basis notes
- Full deck versions when versioning questions were requested
This step is local to the returned JSON. It does not regenerate the analysis packet or call upstream services again.
Step 4 — Set Upgrade (optional)
Select one or more recent MTG sets, or paste a condensed set packet override. The page generates a set-upgrade prompt that references the parsed deck profile and asks your AI to evaluate new cards from each set as potential inclusions, with suggested cuts, bracket-fit notes, speculative tests, and traps called out per set. For Commander/precon-style sets (commander, duel_deck, starter), the packet is filtered to first-print cards only so reprints don't crowd out genuinely new candidates; standard expansions are unfiltered. A deck in Step 1 is required; the parsed Step 3 deck profile is optional but strongly recommended — without it your AI gets an empty schema and produces generic recommendations.
Step 5 — Set Upgrade Results (optional)
Paste the fenced set_upgrade_report JSON block or raw JSON payload returned from your AI. The page validates the payload, parses it into a strongly typed model, and renders a readable summary of:
- Per-set panels: top adds with suggested cuts and reasoning, traps, and speculative tests
- Final shortlist broken into must-test, optional, and skip columns
Like Step 3, this step is local to the returned JSON. You can paste a saved set_upgrade_report JSON file here directly without re-running the earlier steps — Step 5 runs standalone when no deck source is present.
Analysis Question Buckets
Questions are grouped into collapsible buckets. Buckets with pre-selected questions open automatically on page load.
| Bucket | Notable questions |
|---|---|
| Core Deck Analysis | Strengths/weaknesses, win condition, consistency, power level, best meta |
| Deck Construction & Balance | Mana curve, lands and ramp, card draw, interaction count, underperformers |
| Strategy & Synergy | Key synergies, anti-synergies, commander support, protect-cards, game plan |
| Optimization & Upgrades | Cuts for strength, budget upgrades, missing staples, faster/competitive, board-wipe resilience |
| Meta & Matchups | Performance vs. archetypes, pod weaknesses, tech options, hate pieces |
| Play Pattern & Decision Making | Ideal opening hand, tutor priorities, when to cast the commander, common misplays |
| Specific Card-Level Questions | Card worth including and better alternatives can each target multiple card names, and every [card] question is emitted once per card you add; also includes weakest card and too many high-CMC cards |
| Advanced / Expert-Level | Turn clock, disruption vulnerability, keepable hand percentage, redundancy, mana-base optimization |
| Combo Analysis (Commander Spellbook) | Combos already in the deck, combos one card away within the color identity — both use live Commander Spellbook API data injected into the prompt |
| Deck Versioning & Upgrade Paths | Bracket 2/3/4/5 version, 3 named upgrade paths, assign categories, update categories |
Deck Versioning output format
When any versioning or category question is selected, the analysis prompt instructs your AI to:
- Output the full, complete 100-card decklist for each generated version — no truncation, no "fill with basics" shorthand.
- Count cards before responding to confirm the total reaches 100.
- Use the deck builder's inline format when an export format is chosen (Moxfield or Archidekt inline format, with categories when requested).
- Output a Cards Added and Cards Cut diff after each decklist, comparing against the original.
- Output a
deck_profileJSON block for each generated deck version. - When Include card versions is checked, preserve the original printing (set code + collector number) for every retained card.
Category / tag questions
- Assign categories — Your AI assigns functional role categories to every card in the deck. Plain-text export is not supported; Moxfield or Archidekt format is required.
- Update categories — Your AI updates or reassigns categories using the preferred category names you provide. Preferred names are injected into the prompt; your AI may add new categories only when none of the preferred names fit.
- Basic card types (Creature, Instant, Sorcery, Enchantment, Artifact, Planeswalker, Battle) are excluded as categories. Your AI is instructed to use functional role labels instead (Ramp, Card Draw, Removal, Wipe, Tutor, Win Condition, Protection, etc.).
Commander Spellbook combo lookup
When either combo question is selected, the service queries the Commander Spellbook find-my-combos API before building the prompt:
- Returns up to 20 included combos (all pieces are in the deck) and up to 15 almost-included combos (exactly one card missing, within the deck's color identity).
- Each combo entry lists the card names, results, and up to 300 characters of instructions.
- Results are injected as a reference block in the prompt. Your AI is told to treat this data as authoritative.
- API failures degrade gracefully — the analysis continues without combo data rather than failing.
Artifact saving
Use Download session (.zip) in the sticky bar at the top of the page (always available, regardless of step) or in the Step 3 / Step 5 results panel to save the current artifacts locally.
The zip can contain: 00-input-summary.txt, 01-request-context.txt, 30-reference.txt, 31-analysis-prompt.txt, 41-deck-profile-schema.json, 50-set-upgrade-prompt.txt, 40-deck-profile.json, 51-set-upgrade-response.json, all-prompts.txt, and all-responses.txt.
Use Resume from a saved session (.zip) at the top of the page to upload the same zip later. Re-import only reads 40-deck-profile.json and 51-set-upgrade-response.json; the other files remain in the archive for your records.