Add Lexical runtime adapter to Evidence Kit

Objective: Add the next non-Slate runtime adapter after ProseMirror by measuring Lexical headless editor/history operations, wiring the adapter into the active Evidence Kit registry, refreshing generated perf artifacts, and proving the adapter gap count decreases with real rows.

Goal plan: docs/plans/2026-05-28-add-lexical-runtime-adapter-to-evidence-kit.md

Template: docs/plans/templates/major-task.md

Primary template: docs/plans/templates/major-task.md

Applied packs:

• autogoal
• major-task

Major source:

• type: repo benchmark control plane
• id / link: benchmarks/editor/research/benchmark-registry.json
• title: Evidence Kit rich-text runtime adapter matrix
• decision to make: how to add the next non-Slate adapter without claiming browser/product parity
• decision criteria: source-backed target, local clone inspected, active required artifact, measured rows, refreshed docs/health, reduced adapter-missing count

Major lane:

• lane: editor benchmark infrastructure
• output type: adapter implementation plus generated evidence artifacts
• implementation expected: yes
• affected packages / surfaces: benchmarks/editor, generated perf docs, npm lockfile, and this goal plan
• dominant risk: including state reset or browser/product behavior in a headless runtime claim

Completion threshold:

• Lexical has a required active registry artifact.
• npm run bench:adapter:lexical writes at least seven ok rows.
• Rich-text workload coverage marks Lexical ok only for covered headless workload families.
• npm run evidence:refresh refreshes docs, health, and rich-text results.
• Adapter-missing rows drop from 51 to 48; active artifacts rise from 24 to 25; rich-text rows rise from 911 to 918.
• node .agents/rules/autogoal/scripts/check-complete.mjs docs/plans/2026-05-28-add-lexical-runtime-adapter-to-evidence-kit.md passes.

Verification surface:

• /Users/zbeyens/git/plate-2/benchmarks/editor
• local source root /Users/zbeyens/git/lexical
• npm run bench:adapter:lexical
• npm run evidence:refresh
• npm run docs:perf:check
• scoped syntax/lint commands recorded below
• generated benchmarks/results/benchmark-health-latest.json
• generated benchmarks/results/rich-text-editors-latest.json

Constraints:

• Start from local Lexical source before external claims.
• Keep the adapter headless: lexical, @lexical/headless, and @lexical/history.
• Separate measured evidence from source-backed gaps.
• Do not claim React, DOM/browser, collab, or Slate-specific issue parity from a headless Lexical adapter.

Boundaries:

• Source of truth: benchmarks/editor/research/benchmark-registry.json.
• Allowed edit scope: Evidence Kit benchmark package, generated perf artifacts, npm package metadata/lockfile, and this goal plan.
• External sources: none used; local ../lexical source root exists.
• Browser surface: static generated docs at http://127.0.0.1:8765/index.html.
• Tracker sync: none.
• Non-goals: Plate, Tiptap, Lexical React/browser, and Lexical collab adapters.

Blocked condition:

• Autonomous work would stop only if the local Lexical source or npm runtime packages were unavailable, or if the headless adapter could not produce stable measured rows. The adapter ran successfully.

Major state:

• task_type: major
• task_complexity: major
• current_phase: closeout
• current_phase_status: complete
• next_phase: final response
• goal_status: active until final update_goal call

Current verdict:

• verdict: accepted
• confidence: high
• next owner: next adapter task
• reason: Lexical now has active measured runtime rows and the matrix still exposes honest remaining gaps.

Completion rule:

• Do not call update_goal(status: complete) until every completion threshold above is satisfied, final evidence is recorded, and the autogoal check-complete command passes.

Start Gates:

Gate	Applies	Evidence
major-task loaded	yes	task classified as heavyweight benchmark adapter work
Active goal checked or created	yes	active goal created for Lexical adapter threshold
Source of truth read before analysis	yes	registry, package metadata, local Lexical source, README, and generated perf output inspected
Major lane selected	yes	editor benchmark infrastructure
Decision criteria stated	yes	source-backed target, active artifact, measured rows, refreshed docs/health, reduced gaps
Existing repo patterns / prior decisions checked	yes	ProseMirror adapter and iteration notes followed
Helper stack selected	yes	local Node script plus Evidence Kit registry
External research decision recorded	yes	no web research; local Lexical source and package APIs were enough
Implementation expectation recorded	yes	implementation required
Workspace authority selected	yes	/Users/zbeyens/git/plate-2/benchmarks/editor owns commands
Branch / PR expectation decided	yes	no PR requested

Work Checklist:

• Objective includes outcome, completion threshold, verification surface, constraints, boundaries, and blocked condition.
• Major source records source type, id/link, title, decision type, expected outcome, decision criteria, likely files/packages/surfaces, browser surface, and highest-leverage owner.
• Current state is mapped before proposing a new architecture, migration, benchmark, or plan.
• Existing repo patterns, prior decisions, and nearby implementation constraints are recorded before external research.
• External docs or source are used only where repo evidence does not settle the question, or N/A reason is recorded.
• Options, recommendation, tradeoffs, blast radius, and rejection reasons are recorded.
• Facts, inference, and recommendation are separated.
• Review or pressure lenses are selected and completed, or marked N/A with reason.
• Implementation touched benchmark package and docs/evidence surfaces.
• Workspace authority recorded: every proof command names the cwd/tool that owns the analyzed or changed behavior.
• Accepted/actionable review findings are fixed or explicitly rejected with evidence.

Completion Gates:

Gate	Applies	Required action	Evidence
Named verification threshold	yes	Run adapter and refresh commands	npm run bench:adapter:lexical; npm run evidence:refresh
Current-state source audit	yes	Map current owner, boundaries, constraints, and affected surfaces	local Lexical package metadata/source and Evidence Kit registry inspected
Decision criteria closure	yes	Mark each criterion satisfied, narrowed, rejected, or blocked with evidence	Lexical selected for headless runtime coverage only
Options / tradeoffs / rejection record	yes	Record viable options, chosen recommendation, and why alternatives lose	Lexical second; Plate/Tiptap deferred due wrapper/product adapter shape
Review / pressure pass	yes	Validate no overclaiming against workload coverage	React/browser/collab/Slate-specific Lexical rows remain adapter-missing
Review findings closure	yes	Fix or explicitly reject accepted/actionable findings and record closure proof	reset moved outside timed operation samples
External-source audit	yes	Cite official/local clone/external sources when used, or record N/A	local ../lexical exists; local source confirmed headless/history APIs
Implementation gates	yes	Close primary-template and touched-surface gates	adapter, registry, package scripts/deps, generated docs/results updated
Final handoff contract	yes	Record recommendation, evidence, caveats, residual risk, and next owner	see Final handoff contract
Final lint	yes	Run scoped equivalent when files changed	scoped syntax/lint command recorded below
Goal plan complete	yes	Run node .agents/rules/autogoal/scripts/check-complete.mjs docs/plans/2026-05-28-add-lexical-runtime-adapter-to-evidence-kit.md	recorded below

Phase / pass table:

Phase	Status	Evidence	Next
Intake and source read	complete	registry/package/local Lexical source inspected	current-state map
Current-state map	complete	Lexical had source target but no measured runtime rows	options
Options and recommendation	complete	Lexical chosen as second headless runtime adapter; Plate/Tiptap deferred	review
Review / pressure pass	complete	coverage limited to three headless workloads; reset moved out of timed samples	implementation
Implementation or plan artifact	complete	adapter script, registry, package scripts/deps, docs, generated artifacts updated	verification
Verification	complete	focused commands recorded below	closeout
Closeout	complete	final handoff prepared	final response

Findings:

• Lexical exposes a real headless runtime through @lexical/headless.
• Lexical history can be measured headlessly through @lexical/history.
• The adapter can honestly cover large document creation, text insertion, selection, document replacement, block fragment insert, and history undo/redo.
• A headless adapter cannot honestly cover React render behavior, browser replay, collab behavior, or Slate-specific issue #6038 transaction semantics.

Decisions and tradeoffs:

• Chosen: Lexical headless adapter using lexical, @lexical/headless, and @lexical/history.
• Chosen: restore the base editor state before each timed sample, outside the measured callback.
• Deferred: Plate and Tiptap, because those should measure wrapper/product overhead rather than bare runtime cores.
• Rejected: marking all Lexical rows ok; that would fabricate coverage.

Implementation notes:

• Added benchmarks/editor/benchmarks/lexical-runtime-adapter.mjs.
• Added bench:adapter:lexical and wired it into bench:evidence, evidence:refresh, and check.
• Added npm dev dependencies: lexical, @lexical/headless, and @lexical/history.
• Added registry runtimeAdapters metadata and required lexical-runtime-adapter artifact.
• Refreshed generated perf docs/results.

Review fixes:

• Moved Lexical editor-state reset into untimed sample setup so measured rows represent operations, not reset overhead.
• Kept uncovered Lexical browser/product workloads as adapter-missing.

Error attempts:

Error / failed attempt	Count	Next different move	Resolution
Timed callback included Lexical state reset	1	Move reset into sample setup before the timed callback	fixed and reran adapter/refresh

Verification evidence:

• npm install --save-dev [email protected] @lexical/[email protected] @lexical/[email protected] from /Users/zbeyens/git/plate-2/benchmarks/editor: success.
• npm run bench:adapter:lexical from /Users/zbeyens/git/plate-2/benchmarks/editor: success; wrote 7 rows.
• node --check benchmarks/lexical-runtime-adapter.mjs && node --check benchmarks/prosemirror-runtime-adapter.mjs && node --check src/index.mjs from /Users/zbeyens/git/plate-2/benchmarks/editor: success.
• npm run evidence:refresh from /Users/zbeyens/git/plate-2/benchmarks/editor: success; generated 918 rich-text rows and health active=25.
• npm run docs:perf:check from /Users/zbeyens/git/plate-2/benchmarks/editor: success; checked index, evidence, rich-text, and internals docs.
• pnpm exec biome check benchmarks/editor/benchmarks/lexical-runtime-adapter.mjs benchmarks/editor/benchmarks/prosemirror-runtime-adapter.mjs benchmarks/editor/src/index.mjs benchmarks/editor/package.json benchmarks/editor/research/benchmark-registry.json benchmarks/editor/README.md benchmarks/editor/research/evidence-source-map.md benchmarks/editor/iterations/006-lexical-runtime-adapter.md docs/plans/2026-05-28-add-lexical-runtime-adapter-to-evidence-kit.md --fix from /Users/zbeyens/git/plate-2: success; fixed one file.
• Static browser smoke from /Users/zbeyens/git/plate-2: http://127.0.0.1:8765/index.html, rich-text.html, and rich-text-data.json all returned 200.
• node .agents/rules/autogoal/scripts/check-complete.mjs docs/plans/2026-05-28-add-lexical-runtime-adapter-to-evidence-kit.md from /Users/zbeyens/git/plate-2: success.
• Health snapshot: ok=738, adapter-missing=48, coverage-gap=130, optional-missing-artifact=2.
• Lexical workload coverage snapshot: ok for core-rich-text-operations-compare, clipboard-large-payload, and history-compare; adapter-missing remains for React, browser, collab, core-current/core-compare, and issue #6038 workloads.

Final handoff contract:

• Recommendation: next adapter should be Tiptap if the priority is ProseMirror-product-wrapper overhead, or Plate if the priority is direct Plate-vs-Slate user-facing wrapper cost.
• Confidence: high.
• Evidence: active Lexical artifact, generated rows, refreshed docs/health, and explicit workload coverage map.
• Tests / commands: see Verification evidence.
• Browser proof: static generated docs are refreshed for http://127.0.0.1:8765/index.html.
• PR / tracker: no PR requested.
• Caveats: no Lexical DOM/browser, React, or collab adapter yet.
• Next owner: adapter task for Tiptap, Plate, or Lexical DOM depending on the next comparison question.

Timeline:

• 2026-05-28T18:58:18Z Major-task goal plan created.
• 2026-05-28T19:00:00Z Lexical adapter produced first seven rows.
• 2026-05-28T19:04:26Z Evidence Kit docs refreshed with Lexical adapter rows and plan closeout updated.

Reboot status:

Question	Answer
Where am I?	Closeout
Where am I going?	Final verification, goal completion, response
What is the goal?	Add the Lexical non-Slate runtime adapter
What have I learned?	Lexical headless/history can close three workload gaps without overclaiming browser/product coverage
What have I done?	Added adapter, registry metadata, scripts, deps, generated evidence, docs, and iteration note

Open risks:

• Lexical DOM/browser behavior is not measured by this adapter.
• Plate and Tiptap adapter gaps remain.