diff --git a/.changeset/tidy-python-parameters.md b/.changeset/tidy-python-parameters.md
new file mode 100644
index 0000000..e9e544f
--- /dev/null
+++ b/.changeset/tidy-python-parameters.md
@@ -0,0 +1,5 @@
+---
+"@vortexlabs/kirari": patch
+---
+
+Keep Python annotated parameters after commas and unparenthesized lambda parameters inside dictionaries highlighted as variables rather than dictionary keys, including when streaming multiline signatures.
diff --git a/packages/kirari/src/languages/python.ts b/packages/kirari/src/languages/python.ts
index a275b31..2499415 100644
--- a/packages/kirari/src/languages/python.ts
+++ b/packages/kirari/src/languages/python.ts
@@ -1,16 +1,17 @@
 import { definitionsFor } from '../grammars/definitions.js'
 import type { FunctionSyntax } from '../grammars/definitions.js'
 import { scan } from '../tokenize.js'
+import type { ScanContext } from '../tokenize.js'
 import { isSignificant } from '../types.js'
 import type { Language, Token } from '../types.js'
 import { resumableScan } from '../resumable.js'
-import type { ResumableScan } from '../resumable.js'
+import type { PythonScope, ResumableScan } from '../resumable.js'
 
 const tripleString = { type: 'string', pattern: /[rRuUbBfF]{0,2}(?:"""(?:\\(?:[\s\S]|$)|(?!""")[^\\])*(?:"""|$)|'''(?:\\(?:[\s\S]|$)|(?!''')[^\\])*(?:'''|$))/ }
 const fstringOpening = { type: 'python-fstring', pattern: /(?:[fF][rR]?|[rR][fF])(?:"""|'''|"|')/ }
 
 type Literal = { kind: 'literal'; quote: string; raw: boolean; format: boolean }
-type PythonFrame = { kind: 'expression'; depth: number; root?: true } | Literal
+type PythonFrame = { kind: 'expression'; brackets?: PythonScope | undefined; root?: true } | Literal
 
 // Scans literal text in an f-string, stopping at a replacement field or the closing quote.
 const literalChunk = (source: string, start: number, frame: Literal): { end: number; closed: boolean } => {
@@ -62,8 +63,9 @@ const scanLanguage = (language: Language): Language => {
 // Resume points are whitespace at unescaped line breaks, outside f-strings, with more source after them.
 const scanPython: ResumableScan = (source, language, from, checkpoint) => {
   const tokens: Token[] = []
-  const frames: PythonFrame[] = [{ kind: 'expression', depth: 0, root: true }]
-  const scanner = scan(source, scanLanguage(language), from?.offset, from?.previous)
+  const frames: PythonFrame[] = [{ kind: 'expression', brackets: from?.brackets, root: true }]
+  const context: ScanContext = { parentheses: [] }
+  const scanner = scan(source, scanLanguage(language), from?.offset, from?.previous, undefined, [], context)
   let position = from?.offset ?? 0
   let resume: number | undefined
   // Mirrors the scanner's own `previous`, which resuming replaces with a placeholder element.
@@ -87,7 +89,7 @@ const scanPython: ResumableScan = (source, language, from, checkpoint) => {
       if (closed) frames.pop()
       else if (source[position] === '{') {
         emit('punctuation', position + 1)
-        frames.push({ kind: 'expression', depth: 0 })
+        frames.push({ kind: 'expression' })
       } else if (frame.format && source[position] === '}') {
         emit('punctuation', position + 1)
         frames.pop()
@@ -97,6 +99,7 @@ const scanPython: ResumableScan = (source, language, from, checkpoint) => {
     }
 
     if (resume !== undefined && yielded) previous = { type: 'tag', value: 'element', start: yielded.start, end: resume }
+    context.objectKeys = frame.brackets?.value === '{'
     const result = scanner.next(resume)
     resume = undefined
     if (result.done) break
@@ -108,7 +111,7 @@ const scanPython: ResumableScan = (source, language, from, checkpoint) => {
       const merged = last?.type === 'text'
       // A backslash in source text continues the line; one inside a comment does not.
       if (!merged || !last.value.endsWith('\\')) {
-        checkpoint({ offset: merged ? last.start : position, previous }, merged ? tokens.length - 1 : tokens.length)
+        checkpoint({ offset: merged ? last.start : position, previous, brackets: frame.brackets }, merged ? tokens.length - 1 : tokens.length)
       }
     }
     const opening = token.type === fstringOpening.type && /^(f|fr|rf)("""|'''|"|')$/i.exec(token.value)
@@ -117,7 +120,7 @@ const scanPython: ResumableScan = (source, language, from, checkpoint) => {
       frames.push({ kind: 'literal', quote: opening[2]!, raw: /r/i.test(opening[1]!), format: false })
       continue
     }
-    if (!frame.root && frame.depth === 0) {
+    if (!frame.root && !frame.brackets) {
       if (token.value === '}') {
         emit('punctuation', token.end)
         frames.pop()
@@ -136,10 +139,9 @@ const scanPython: ResumableScan = (source, language, from, checkpoint) => {
         continue
       }
     }
-    if (token.type === 'punctuation') {
-      if (/^[([{]$/.test(token.value)) frame.depth++
-      else if (/^[)\]}]$/.test(token.value) && frame.depth > 0) frame.depth--
-    }
+    if (token.type === 'keyword' && token.value === 'lambda' || token.type === 'punctuation' && /^[([{]$/.test(token.value)) {
+      frame.brackets = { value: token.value, parent: frame.brackets }
+    } else if (token.type === 'punctuation' && (/^[)\]}]$/.test(token.value) || token.value === ':' && frame.brackets?.value === 'lambda')) frame.brackets = frame.brackets?.parent
     emit(token.type, token.end)
   }
   return tokens
diff --git a/packages/kirari/src/resumable.ts b/packages/kirari/src/resumable.ts
index 10869e3..1076936 100644
--- a/packages/kirari/src/resumable.ts
+++ b/packages/kirari/src/resumable.ts
@@ -1,10 +1,14 @@
 import type { ScanContext } from './tokenize.js'
 import type { Language, Token } from './types.js'
 
+export type PythonScope = { readonly value: string; readonly parent: PythonScope | undefined }
+
 /** A root-level point where scanning can restart with the same results as a full scan. */
 export type ResumePoint = {
   readonly offset: number
   readonly previous: Token | undefined
+  /** Immutable Python delimiters and lambda parameter scopes shared with later checkpoints. */
+  readonly brackets?: PythonScope | undefined
   /** Script scan state at the point, for grammars that embed JavaScript. */
   readonly context?: ScanContext
 }
diff --git a/packages/kirari/src/tokenize.ts b/packages/kirari/src/tokenize.ts
index b84c822..5e66f7e 100644
--- a/packages/kirari/src/tokenize.ts
+++ b/packages/kirari/src/tokenize.ts
@@ -21,9 +21,11 @@ import type { FunctionLookupCache } from './grammars/functions.js'
 import { canStartRegex, escapedIdentifierEnd, nextVisibleChar, regexEnd, templateChunk } from './scanner/lexical.js'
 
 export type Frame = { kind: 'template'; opening: boolean } | { kind: 'expression'; depth: number }
-/** Lexical state for JavaScript-like languages, carried between scanner steps. */
+/** Lexical state carried between scanner steps, including context supplied by embedded grammars. */
 export type ScanContext = {
   parentheses: { control: boolean; braces: number }[]
+  /** Unset keeps the generic comma-separated key heuristic. */
+  objectKeys?: boolean
   braces?: number
   afterControl?: boolean
   forAwait?: boolean
@@ -240,7 +242,7 @@ export function* scan(source: string, language: Language, start = 0, previous?:
       else if (types.has(name) || previous?.value === 'class' || typed && (context.annotation || previous?.type === 'keyword' && /^(type|interface|enum)$/.test(previous.value))) type = 'type'
       else {
         const following = nextVisibleChar(source, end)
-        if (following === ':' && (previous?.value === '{' || previous?.value === ',' || typed && method && previous?.value === ';')) type = 'property' // { name: value } or TypeScript members
+        if (following === ':' && (previous?.value === '{' || previous?.value === ',' && context.objectKeys !== false || typed && method && previous?.value === ';')) type = 'property' // { name: value } or TypeScript members
         else if (following === '(') type = 'function' // name(…)
       }
       // Look ahead for definitions such as `name = () => …` or `name: function () {}`.
diff --git a/packages/kirari/test/corpus/fixtures.ts b/packages/kirari/test/corpus/fixtures.ts
index f8e6494..319f031 100644
--- a/packages/kirari/test/corpus/fixtures.ts
+++ b/packages/kirari/test/corpus/fixtures.ts
@@ -268,6 +268,26 @@ export const corpus: readonly CorpusFixture[] = [
       { text: 'rows', type: 'attribute' },
     ],
   },
+  {
+    id: 'python-typed-parameters-and-dictionary-keys', language: 'python',
+    source: 'def typed(\n    first: tuple[int, str],\n    second: str,\n    defaults={key1: {inner: 1}, key2: 2},\n):\n    return defaults.member\n',
+    assertions: [
+      { text: 'typed', type: 'function' }, { text: 'first', type: 'variable' },
+      { text: 'second', type: 'variable' }, { text: 'defaults', type: 'variable', occurrence: 0 },
+      { text: 'key1', type: 'property' }, { text: 'inner', type: 'property' },
+      { text: 'key2', type: 'property' }, { text: 'member', type: 'property' },
+    ],
+  },
+  {
+    id: 'python-dictionary-lambda-parameters', language: 'python',
+    source: 'handlers = {\n    first: lambda left,\n        right: 1,\n    second: lambda value={key: 2},\n        other: 3,\n}\n',
+    assertions: [
+      { text: 'first', type: 'property' }, { text: 'second', type: 'property' },
+      { text: 'left', type: 'variable' }, { text: 'right', type: 'variable' },
+      { text: 'value', type: 'variable' }, { text: 'other', type: 'variable' },
+      { text: 'key', type: 'property' },
+    ],
+  },
   {
     id: 'python-function-and-values', language: 'python',
     source: 'def select_route(routes):\n    for route in routes:\n        if route.enabled:\n            return True\n    return None # no match\n',
diff --git a/packages/kirari/test/language-performance.test.ts b/packages/kirari/test/language-performance.test.ts
index 56a64f6..cb844f9 100644
--- a/packages/kirari/test/language-performance.test.ts
+++ b/packages/kirari/test/language-performance.test.ts
@@ -5,6 +5,8 @@ import { csharp } from '../src/languages/csharp.js'
 import { php } from '../src/languages/php.js'
 import { css } from '../src/languages/css.js'
 import { javascript } from '../src/languages/javascript.js'
+import { python } from '../src/languages/python.js'
+import { resumableScanOf } from '../src/resumable.js'
 import { jsx } from '../src/languages/jsx.js'
 import { makefile } from '../src/languages/makefile.js'
 import { toml } from '../src/languages/toml.js'
@@ -12,6 +14,16 @@ import { yaml } from '../src/languages/yaml.js'
 import { createMarkdown } from '../src/markdown.js'
 import { createRegistry } from '../src/registry.js'
 
+test('Python checkpoints avoid copying growing delimiter stacks on incomplete input', () => {
+  const source = '(\n'.repeat(75_000) + 'value'
+  let checkpoints = 0
+  const start = performance.now()
+  const tokens = resumableScanOf(python)!(source, python, undefined, () => checkpoints++)
+  expect(tokens.map(token => token.value).join('')).toBe(source)
+  expect(checkpoints).toBe(75_000)
+  expect(performance.now() - start).toBeLessThan(1500)
+}, 10_000)
+
 test('JSX expression lookups do not repeatedly search the full source for absent line separators', () => {
   const source = '<div>' + '{x}\n'.repeat(64_000) + '</div>'
   const start = performance.now()
diff --git a/packages/kirari/test/python-accuracy.test.ts b/packages/kirari/test/python-accuracy.test.ts
index 25f038f..ef37c54 100644
--- a/packages/kirari/test/python-accuracy.test.ts
+++ b/packages/kirari/test/python-accuracy.test.ts
@@ -4,6 +4,49 @@ import { python } from '../src/languages/python.js'
 
 const pairs = (source: string) => tokenize(source, python).map(token => [token.type, token.value])
 
+test.each([
+  'def f(a: str, b: str): pass',
+  'def f(a, b: str): pass',
+  'def f(a: str, b): pass',
+  'async def f(a: tuple[int, str], b: str): pass',
+  'def f(a={k1: 1, k2: 2}, b: str): pass',
+  'def f(\n    a: str, # first\n    b: str,\n): pass',
+])('Python keeps annotated parameters as variables in %j', source => {
+  const result = pairs(source)
+  for (const name of ['a', 'b']) {
+    expect(result).toContainEqual(['variable', name])
+    expect(result).not.toContainEqual(['property', name])
+  }
+})
+
+test('Python distinguishes dictionary keys, members, and lambda parameters in nested expressions', () => {
+  const result = pairs('def f(a={k1: {inner: 1}, k2: (lambda x, y: obj.attr)}, b: str): pass')
+  for (const name of ['k1', 'inner', 'k2', 'attr']) expect(result).toContainEqual(['property', name])
+  for (const name of ['a', 'b', 'x', 'y']) expect(result).toContainEqual(['variable', name])
+})
+
+test.each([
+  "x = {'f': lambda a, b: 1, next: 2}",
+  "x = {'f': lambda a={key: 1}, b: 1, next: 2}",
+  "x = {'f': lambda a=lambda c, d: 1, b: 2, next: 3}",
+  "x = {'f': lambda a,\n    b: 1,\n    next: 2}",
+  'f"{ {key: lambda a, b: 1, next: 2} }"',
+])('Python keeps unparenthesized lambda parameters out of dictionary keys in %j', source => {
+  const result = pairs(source)
+  expect(result).toContainEqual(['variable', 'b'])
+  expect(result).not.toContainEqual(['property', 'b'])
+  expect(result).toContainEqual(['property', 'next'])
+  if (source.includes('lambda c')) expect(result).toContainEqual(['variable', 'd'])
+  if (source.includes('key:')) expect(result).toContainEqual(['property', 'key'])
+})
+
+test('Python bracket context preserves explicit property rules before identifier classification', () => {
+  const language = { ...python, rules: [{ type: 'property', pattern: /SPECIAL/ }, ...python.rules] }
+  const tokens = tokenize('def f(a, SPECIAL: str, b: str): pass', language)
+  expect(tokens).toContainEqual({ type: 'property', value: 'SPECIAL', start: 9, end: 16 })
+  expect(tokens).toContainEqual({ type: 'variable', value: 'b', start: 23, end: 24 })
+})
+
 test('Python f-strings expose expression variables, members, calls, and operators', () => {
   const result = pairs('label = f"Arrival {station.name}: {count + 1} {format(delay)} 🚉"')
   for (const pair of [['variable', 'station'], ['property', 'name'], ['variable', 'count'],
diff --git a/packages/kirari/test/stream.test.ts b/packages/kirari/test/stream.test.ts
index f2a16ff..8502d38 100644
--- a/packages/kirari/test/stream.test.ts
+++ b/packages/kirari/test/stream.test.ts
@@ -110,6 +110,24 @@ test('Python streams keep definitions that later lines can still change revisabl
   }
 })
 
+test('Python line checkpoints bound rescanning inside multiline brackets', () => {
+  for (const source of [
+    'def f(\n' + '    arg: str,\n'.repeat(200) + '): pass\n',
+    'values = {\n' + '    key: (lambda a, b: b),\n'.repeat(200) + '}\n',
+  ]) {
+    const stream = createTokenStream(python)
+    const tokens: Token[] = []
+    let work = 0
+    for (let start = 0; start < source.length; start += 4) {
+      const patch = stream.write(source.slice(start, start + 4))
+      work += patch.length - patch.from
+      apply(tokens, patch)
+    }
+    expect(tokens).toEqual(tokenize(source, python))
+    expect(work).toBeLessThan(source.length * 20)
+  }
+})
+
 test('Python line checkpoints bound rescanning', () => {
   const blocks = [
     'def greet(name: str) -> str:\n    return f"Hello, {name}!"  # note\n',
diff --git a/sites/docs/changelog/kirari/1.1.4.md b/sites/docs/changelog/kirari/1.1.4.md
new file mode 100644
index 0000000..65fdce9
--- /dev/null
+++ b/sites/docs/changelog/kirari/1.1.4.md
@@ -0,0 +1,10 @@
+---
+package: kirari
+version: 1.1.4
+date: 2026-10-22
+---
+
+### Bug fixes
+
+- Python annotated parameters after commas, such as `b` in `def f(a: str, b: str): pass`, are highlighted as variables instead of dictionary keys. Multiline signatures keep the same highlighting when streamed.
+- Unparenthesized lambda parameters inside dictionaries, such as `b` in `{'f': lambda a, b: 1}`, keep their variable highlighting, including across streamed line breaks.