Here's the updated inventory in the exact same format — only changed items that the code now supports:

Kitty Graphics Protocol — Feature Inventory

Spec: https://sw.kovidgoyal.net/kitty/graphics-protocol/

Coming from: #5619

Key files:

• Handler: KittyGraphicsHandler.ts
• Types: KittyGraphicsTypes.ts
• KittyImageStorage: KittyImageStorage.ts
• ImageStorage: ImageStorage.ts
• ImageRenderer: ImageRenderer.ts
• Integration tests: KittyGraphics.test.ts

flowchart TD
 A["Shell sends Kitty escape sequence<br/>ESC _ G a=T,f=32,s=2,v=2,i=1;<br/>base64... ESC \\"]
 A --> B

 B["ApcParser matches 'G'<br/>→ KittyGraphicsHandler<br/>registered in ImageAddon.ts"]
 B --> C

 C["start — reset state"]
 C --> D

 D["put — two-phase parsing<br/>1. Scan for semicolon,<br/>buffer keys<br/>2. parseKittyCommand<br/>extracts keys<br/>3. Stream payload into<br/>Base64Decoder"]
 D --> E

 E["end — finalize"]

 E --> F{"More chunks?<br/>m=1"}
 F -->|"Yes"| G["Park decoder in<br/>_pendingTransmissions<br/>keeps decoder alive<br/>across sequences"]
 G -.->|"Next sequence"| C
 F -->|"No"| H{"Action?"}

 H -->|"a=t transmit"| I["_handleTransmit<br/>KittyImageStorage.storeImage<br/>Blob copies bytes off JS heap"]
 H -->|"a=T transmit+display"| J["_handleTransmitDisplay<br/>storeImage as Blob<br/>then render"]
 H -->|"a=q query"| K["_handleQuery<br/>validate format/size<br/>respond OK or EINVAL"]
 H -->|"a=p placement"| P["_handlePlacement<br/>getImage from storage<br/>_displayImage<br/>respond OK or ENOENT"]
 H -->|"a=d delete"| L

 J --> M["_decodeAndDisplay"]
 P --> M
 M --> M1{"Image format?"}
 M1 -->|"f=100 PNG"| M1a["Wrap as image/png Blob<br/>browser decodes natively"]
 M1 -->|"f=32 RGBA"| M1b["Raw bytes → ImageData<br/>already has alpha"]
 M1 -->|"f=24 RGB"| M1c["uint32 block interleave<br/>RGB → RGBA<br/>adds alpha=0xFF000000"]
 M1a --> CROP
 M1b --> CROP
 M1c --> CROP
 CROP["Source crop x,y,w,h<br/>createImageBitmap crop<br/>if specified"]
 CROP --> BMP
 BMP["createImageBitmap<br/>GPU-backed render-ready<br/>object for efficient<br/>canvas drawing"]
 BMP --> M2["Resize via<br/>createImageBitmap<br/>if c/r columns/rows<br/>specified"]
 M2 --> OFFSET["Sub-cell offset X,Y<br/>Composite onto padded<br/>canvas if specified"]
 OFFSET --> M3["KittyImageStorage.addImage<br/>→ ImageStorage.addImage<br/>Tiles bitmap into cells,<br/>marks each with<br/>image+tile ID.<br/>Adds scroll marker<br/>for cleanup."]
 M3 --> M4["KittyImageStorage<br/>bridges Kitty ID<br/>→ internal storage ID<br/>via _kittyIdToStorageId<br/>+ _storageIdToKittyId"]
 M4 --> M5{"Cursor<br/>movement<br/>C key"}
 M5 -->|"C=0 default"| M6["Advance cursor<br/>past image"]
 M5 -->|"C=1"| M7["Restore cursor<br/>with scroll correction"]

 subgraph LAYER["Layer Selection"]
   Z1{"z key?"}
   Z1 -->|"z < 0"| Z2["bottom layer<br/>(behind text)"]
   Z1 -->|"z >= 0 or absent"| Z3["top layer<br/>(on top of text)"]
 end
 M2 --> Z1
 Z2 --> M3
 Z3 --> M3

 subgraph DEL["_handleDelete — selector dispatch"]
   L1{"d key selector?"}
   L1 -->|"d=a / d=A"| L2["Abort ALL in-flight decoders<br/>KittyImageStorage.deleteAll()"]
   L1 -->|"d=i / d=I"| L3["Abort targeted decoder<br/>KittyImageStorage.deleteById()"]
   L1 -->|"default (no d key)"| L2
   L1 -->|"other (c,n,p,…)"| L4["Ignored (not yet supported)"]
   L2 --> L5["Delete Blob from _images<br/>Delete bitmap from ImageStorage<br/>Clear kittyId↔storageId maps"]
   L3 --> L5
 end
 L --> L1

 subgraph EVICT["Eviction & Cleanup (KittyImageStorage)"]
   EV1["onImageDeleted callback<br/>fires when ImageStorage<br/>evicts/deletes an image"]
   EV1 --> EV2["_handleStorageImageDeleted<br/>cleans _kittyIdToStorageId<br/>_storageIdToKittyId<br/>_images"]
   EV3["storeImage with same ID<br/>deletes old placement<br/>from ImageStorage first"]
   EV4["_evictUndisplayedImages<br/>when _images exceeds 256<br/>preferentially removes<br/>images without placements"]
 end

 I --> RESP
 M5 --> RESP
 K --> RESP

 RESP["_sendResponse<br/>OK or EINVAL to client<br/>q=1 suppresses OK<br/>q=2 suppresses errors"]
 RESP --> DONE["Client receives response"]

Legend: ✅ Done | ⚠️ Partial | ❌ TODO | 🚫 Blocked (renderer/architecture limitation)

1. Escape Code Format (APC)

2. Actions (a key)

3. Image Formats (f key)

4. Transmission Medium (t key)

5. Compression (o key)

6. Chunked Transmission (m key)

7. Image Display Layout

8. Image IDs & Placement IDs

9. Delete Commands (a=d, d key)

10. Response / Acknowledgement System

11. Unicode Placeholders

12. Relative Placements

13. Animation

14. Terminal Interaction

15. Memory & Storage

16. Control Data Keys — Parse Status

MVP Checklist (Feb 9 – 20)

Items from the chart above that need work before initial merge. Ordered by priority.

P0 — Clients break without these

• §7.5 — Cursor movement — C key parsed. Default (C=0): cursor at (originX + cols, lastRow). C=1: cursor restored. Fixed proportional resize to spec-correct stretch. 10 integration tests (5 unskipped + 5 updated). 2 unit tests for C key parsing.

P1 — Important for correctness

• §9.13 — Strict malformed sequence handling — Abort on invalid keys, unexpected payload. Document policy. (PR feedback)
• Share Base64Decoder with IIP — Both KittyGraphicsHandler and IIPHandler create independent wasm Base64Decoder instances. Avoid duplicate wasm memory. (PR feedback)

Done

• §2.4 — a=p (Put/Display previously transmitted) — _handlePlacement retrieves stored image via _kittyStorage.getImage(), calls _displayImage() with full display pipeline (crop, resize, offset, z-index, cursor). Responds OK on success, ENOENT when image not found. Supports c/r, C, z, x/y/w/h, X/Y, and placement ID in response. 20 integration tests.
• §7.3 — Source rectangle crop (x, y, w, h) — x, y as crop origin. w, h parsed as sourceWidth/sourceHeight for crop dimensions. Uses createImageBitmap(bitmap, cropX, cropY, finalCropW, finalCropH). Out-of-bounds x/y produces no display. w=0/h=0 treated as unset. Negative values clamped to 0. Combinable with c/r and X/Y. 8 integration tests.
• §7.4 — Cell-offset within first cell (X, Y) — X/Y parsed as xOffset/yOffset. Composited onto padded canvas. Clamped to cell dimensions. When c/r explicit, placement area stays c×cw × r×ch and offset image is clipped. Without c/r, padded canvas determines natural cell dimensions. 4 integration tests.
• §7.6 — z-index sorted rendering — Draw calls sorted by z-index so lower z draws first and higher z renders on top within each layer.
• §8.5 — Placement ID in responses — _sendResponse includes ,p=<pid> when placementId provided. 1 integration test.
• §8.6 — Multiple placements of same image — a=p allows placing same transmitted image at different cursor positions. Each placement creates separate ImageStorage entry. Image data persists across placements. 2 integration tests.
• §10.6 — ENOENT response for a=p — _handlePlacement sends ENOENT:image not found when image not in storage. q=1 still reports ENOENT (only suppresses OK). q=2 suppresses ENOENT. 3 integration tests.
• §10.7 — Placement ID in response — _sendResponse includes ,p=<pid> when placementId provided. 1 integration test verifying \x1b_Gi=224,p=42;OK\x1b\\ format.
• §8.7 — outsideId → storageId map — KittyImageStorage manages bidirectional _kittyIdToStorageId / _storageIdToKittyId. onImageDeleted callback keeps maps in sync when ImageStorage evicts. Delete cascades to ImageStorage.
• §8.8 — Re-transmit same ID cleanup — KittyImageStorage.storeImage() checks for existing _kittyIdToStorageId entry and calls _storage.deleteImage() on old placement before storing new data. 2 integration tests.
• §9.1-9.2 — Parse d key + delete dispatch — DELETE_SELECTOR and PLACEMENT_ID added to KittyKey. deleteSelector parsed as string, placementId parsed as number. _handleDelete dispatches via switch/case: d=a/d=A → KittyImageStorage.deleteAll(), d=i/d=I → KittyImageStorage.deleteById(). Default selector is 'a' per spec. d=a aborts all in-flight uploads; d=i aborts only targeted upload. 7 unit tests for d/p key parsing. 14 integration tests for delete dispatch including pixel-level verification. TODOs for lowercase/uppercase distinction.
• §9.2 — Delete by ID cascades to ImageStorage — KittyImageStorage.deleteById() calls _storage.deleteImage() for displayed images.
• deleteImage() public API on ImageStorage — Thin wrapper around _delImg + marker dispose.
• f=24/f=32 integration tests — 27 tests with pixel verification, storage, dimensions.
• §10.2 — Send OK for a=t / a=T — a=t sends OK in dispatcher after _handleTransmit. a=T sends OK after async display via .then(). Only when cmd.id provided. Respects q=1/q=2.
• §3.1 — Fix default format — _handleTransmit now defaults to KittyFormat.RGBA (f=32) per spec instead of PNG.
• §3.2 — Bit-shift RGB→RGBA — uint32 block interleave: 3 uint32 reads + 4 uint32 writes per 4 pixels vs 28 byte reads/writes — ~6× faster. Remainder pixels handled byte-by-byte.
• §9.14 — Abort in-flight chunks on delete — _handleDelete releases decoders and clears _pendingTransmissions. d=a/d=A aborts all; d=i/d=I aborts only targeted. 4 integration tests.
• §7.5 — Cursor movement — C key parsed. Default (C=0): cursor at (originX + cols, lastRow). C=1: cursor restored. Fixed proportional resize to spec-correct stretch. 10 integration tests (5 unskipped + 5 updated). 2 unit tests for C key parsing.
• §14.2 — Clean up Kitty blobs on ESC[2J — ImageStorage's marker disposal fires onImageDeleted callback → KittyImageStorage._handleStorageImageDeleted cascades cleanup to _images, _kittyIdToStorageId, _storageIdToKittyId. No more stale entries.
• §14.3 — Clean up Kitty blobs on alt buffer switch — ImageStorage's wipeAlternate() calls _delImg() which fires onImageDeleted → KittyImageStorage._handleStorageImageDeleted cleans kitty maps. Fully cascaded.
• §15.1 — Storage eviction keeps kitty maps clean — KittyImageStorage enforces _maxStoredImages = 256 cap with _evictUndisplayedImages(). onImageDeleted callback keeps kitty maps in sync when ImageStorage evicts by pixel limit or scrollback. 2 integration tests (memory limit eviction, scrollback eviction).
• §15.4 — Preferentially delete images without placements — KittyImageStorage._evictUndisplayedImages() preferentially removes images that have no _kittyIdToStorageId entry.
• §7.6 — z-index layer selection — z key parsed. Negative z → bottom layer (behind text), z≥0 → top layer. ImageStorage.addImage() accepts layer and zIndex params. Draw calls sorted by z-index. 9 integration tests including DOM order verification.
• §4.1 — t key parsing + rejection — t key parsed as transmission via KittyKey.TRANSMISSION. t=d accepted; t=f/t=t/t=s rejected with EINVAL for both transmit and query actions. 13 integration tests.