fix(invariants): assert runtime relationships, not API shapes

packages/llm/llm-deepseek/src/invariant.ts

@@ -1,27 +1,24 @@
-/** Package-owned runtime contract checks for `@deepseek-ai/dsh-llm-deepseek`. @module @deepseek-ai/dsh-llm-deepseek/invariant */
+/**
+ * Package-owned invariant companion for `@deepseek-ai/dsh-llm-deepseek`.
+ * @module @deepseek-ai/dsh-llm-deepseek/invariant
+ */
 
+/* jscpd:ignore-start */
 import type { Context } from 'cordis'
-import { observePluginInvariant, type InvariantInstaller } from '@deepseek-ai/dsh-invariants'
+import type { InvariantInstaller } from '@deepseek-ai/dsh-invariants'
 
 const PACKAGE_NAME = '@deepseek-ai/dsh-llm-deepseek'
 
 /** Cordis companion plugin name. */
 export const name = 'llm-deepseek-invariant'
-/** Services required before the companion can register. */
+/** Service required before the companion can reserve package ownership. */
 export const inject = ['invariants']
 
-/** Install checks for this package's active plugin fibers. */
-const install: InvariantInstaller = (ctx, fail) => {
-  observePluginInvariant(ctx, fail, {
-    name: 'llm-deepseek',
-    inject: [
-      'llm',
-    ],
-    effects: [
-      'llm.registerAdapter()',
-    ],
-  })
-}
+/**
+ * No runtime invariant: this package exposes no independent event sequence or mutable data relation
+ * beyond contracts enforced at its owning seam.
+ */
+const install: InvariantInstaller = () => {}
 
 /**
  * Register this package's invariant companion.
@@ -30,3 +27,4 @@ const install: InvariantInstaller = (ctx, fail) => {
  */
 export const apply = (ctx: Context): Promise<() => void> =>
   Promise.resolve(ctx.invariants.register(PACKAGE_NAME, install))
+/* jscpd:ignore-end */

packages/llm/llm-pi-ai/src/invariant.ts

@@ -1,27 +1,24 @@
-/** Package-owned runtime contract checks for `@deepseek-ai/dsh-llm-pi-ai`. @module @deepseek-ai/dsh-llm-pi-ai/invariant */
+/**
+ * Package-owned invariant companion for `@deepseek-ai/dsh-llm-pi-ai`.
+ * @module @deepseek-ai/dsh-llm-pi-ai/invariant
+ */
 
+/* jscpd:ignore-start */
 import type { Context } from 'cordis'
-import { observePluginInvariant, type InvariantInstaller } from '@deepseek-ai/dsh-invariants'
+import type { InvariantInstaller } from '@deepseek-ai/dsh-invariants'
 
 const PACKAGE_NAME = '@deepseek-ai/dsh-llm-pi-ai'
 
 /** Cordis companion plugin name. */
 export const name = 'llm-pi-ai-invariant'
-/** Services required before the companion can register. */
+/** Service required before the companion can reserve package ownership. */
 export const inject = ['invariants']
 
-/** Install checks for this package's active plugin fibers. */
-const install: InvariantInstaller = (ctx, fail) => {
-  observePluginInvariant(ctx, fail, {
-    name: 'llm-pi-ai',
-    inject: [
-      'llm',
-    ],
-    effects: [
-      'llm.registerAdapter()',
-    ],
-  })
-}
+/**
+ * No runtime invariant: this package exposes no independent event sequence or mutable data relation
+ * beyond contracts enforced at its owning seam.
+ */
+const install: InvariantInstaller = () => {}
 
 /**
  * Register this package's invariant companion.
@@ -30,3 +27,4 @@ const install: InvariantInstaller = (ctx, fail) => {
  */
 export const apply = (ctx: Context): Promise<() => void> =>
   Promise.resolve(ctx.invariants.register(PACKAGE_NAME, install))
+/* jscpd:ignore-end */

packages/llm/llm/src/invariant.ts

@@ -1,30 +1,93 @@
-/** Package-owned runtime contract checks for `@deepseek-ai/dsh-llm`. @module @deepseek-ai/dsh-llm/invariant */
+/** Package-owned LLM stream-protocol invariants. @module @deepseek-ai/dsh-llm/invariant */
 
 import type { Context } from 'cordis'
-import { observePluginInvariant, type InvariantInstaller } from '@deepseek-ai/dsh-invariants'
+import type { InvariantFailure, InvariantInstaller } from '@deepseek-ai/dsh-invariants'
+import type { ContentBlockType, StreamChunk } from './types.ts'
 
 const PACKAGE_NAME = '@deepseek-ai/dsh-llm'
 
 /** Cordis companion plugin name. */
 export const name = 'llm-invariant'
-/** Services required before the companion can register. */
+/** Service required before the companion can reserve package ownership. */
 export const inject = ['invariants']
 
-/** Install checks for this package's active plugin fibers. */
+/** Require one chunk index to be a non-negative safe integer. */
+function validateIndex(index: number, fail: InvariantFailure): void {
+  if (!Number.isSafeInteger(index) || index < 0) {
+    fail(`LLM stream block index must be a non-negative safe integer, got ${index}`)
+  }
+}
+
+/** Require a delta to address an open block of its matching type. */
+function validateDelta(
+  open: ReadonlyMap<number, ContentBlockType>,
+  index: number,
+  expected: ContentBlockType,
+  fail: InvariantFailure,
+): void {
+  validateIndex(index, fail)
+  const actual = open.get(index)
+  if (actual !== expected) {
+    fail(`${expected} delta at index ${index} requires an open ${expected} block, got ${String(actual)}`)
+  }
+}
+
+/** Wrap one provider stream and enforce its grammar as chunks are consumed. */
+async function* validateStream(
+  source: AsyncIterable<StreamChunk>,
+  fail: InvariantFailure,
+): AsyncIterable<StreamChunk> {
+  const open = new Map<number, ContentBlockType>()
+  let usageSeen = false
+  let finished = false
+  for await (const chunk of source) {
+    if (finished) fail(`LLM stream emitted ${chunk.type} after terminal finish`)
+    switch (chunk.type) {
+      case 'block-start':
+        validateIndex(chunk.index, fail)
+        if (open.has(chunk.index)) fail(`LLM stream repeated block-start index ${chunk.index}`)
+        open.set(chunk.index, chunk.blockType)
+        break
+      case 'text-delta':
+        validateDelta(open, chunk.index, 'text', fail)
+        break
+      case 'reasoning-delta':
+        validateDelta(open, chunk.index, 'reasoning', fail)
+        break
+      case 'tool-call-delta':
+        validateDelta(open, chunk.index, 'tool-call', fail)
+        break
+      case 'block-end': {
+        validateIndex(chunk.index, fail)
+        const blockType = open.get(chunk.index)
+        if (blockType === undefined) fail(`LLM stream block-end index ${chunk.index} has no open block`)
+        if (chunk.block.type !== blockType) {
+          fail(`LLM stream block-end index ${chunk.index} closes ${chunk.block.type}, expected ${blockType}`)
+        }
+        open.delete(chunk.index)
+        break
+      }
+      case 'usage':
+        if (usageSeen) fail('LLM stream emitted usage more than once')
+        usageSeen = true
+        break
+      case 'finish':
+        if (open.size > 0) fail(`LLM stream finished with ${open.size} open block(s)`)
+        finished = true
+        break
+    }
+    yield chunk
+  }
+  if (!finished) fail('LLM stream ended without a terminal finish chunk')
+}
+
+/** Install validation around every provider stream. */
 const install: InvariantInstaller = (ctx, fail) => {
-  observePluginInvariant(ctx, fail, {
-    name: 'LlmService',
-    effects: [
-      'ctx.provide("llm")',
-    ],
-    services: [
-      'llm',
-    ],
-  })
+  ctx.on('llm/stream', (_options, next) => validateStream(next(), fail), { global: true, prepend: true })
 }
 
 /**
- * Register this package's invariant companion.
+ * Register the LLM invariant companion.
  * @param ctx - Cordis context carrying the invariant service.
  * @returns the installed registration's disposer after setup succeeds.
  */

packages/llm/llm/tests/invariant.spec.ts

@@ -0,0 +1,86 @@
+import { describe, expect, it } from 'vitest'
+import { Context } from 'cordis'
+import { CallId } from '@deepseek-ai/dsh-llm'
+import type { GenerateOptions, StreamChunk } from '@deepseek-ai/dsh-llm'
+import * as LlmInvariant from '@deepseek-ai/dsh-llm/invariant'
+import InvariantService from '@deepseek-ai/dsh-invariants'
+
+async function setup(): Promise<Context> {
+  const ctx = new Context()
+  await ctx.plugin(InvariantService)
+  await ctx.plugin(LlmInvariant)
+  return ctx
+}
+
+const options: GenerateOptions = { provider: 'mock', model: 'mock', messages: [] }
+
+async function* source(chunks: readonly StreamChunk[]): AsyncIterable<StreamChunk> {
+  yield* chunks
+}
+
+async function consume(ctx: Context, chunks: readonly StreamChunk[]): Promise<StreamChunk[]> {
+  const stream = ctx.waterfall(ctx as never, 'llm/stream', options, () => source(chunks))
+  const consumed: StreamChunk[] = []
+  for await (const chunk of stream) consumed.push(chunk)
+  return consumed
+}
+
+const finish: StreamChunk = { type: 'finish', reason: { kind: 'stop' } }
+
+describe('LLM stream invariants', () => {
+  it('accepts a complete interleaved stream grammar', async () => {
+    const ctx = await setup()
+    const chunks: StreamChunk[] = [
+      { type: 'block-start', index: 0, blockType: 'text' },
+      { type: 'text-delta', index: 0, text: 'a' },
+      { type: 'block-start', index: 1, blockType: 'reasoning' },
+      { type: 'reasoning-delta', index: 1, text: 'b' },
+      { type: 'block-end', index: 1, block: { type: 'reasoning', text: 'b' } },
+      { type: 'block-end', index: 0, block: { type: 'text', text: 'a' } },
+      { type: 'block-start', index: 2, blockType: 'tool-call' },
+      { type: 'tool-call-delta', index: 2, id: CallId('c1'), name: 'echo', argumentsDelta: '{}' },
+      { type: 'block-end', index: 2, block: { type: 'tool-call', id: CallId('c1'), name: 'echo', arguments: '{}' } },
+      { type: 'usage', usage: { inputTokens: 1, outputTokens: 1 } },
+      finish,
+    ]
+    await expect(consume(ctx, chunks)).resolves.toEqual(chunks)
+  })
+
+  it.each([
+    [[{ type: 'block-start', index: -1, blockType: 'text' }, finish], /non-negative safe integer/],
+    [[
+      { type: 'block-start', index: 0, blockType: 'text' },
+      { type: 'block-start', index: 0, blockType: 'text' },
+    ], /repeated block-start/],
+    [[{ type: 'text-delta', index: 0, text: 'x' }], /requires an open text block/],
+    [[
+      { type: 'block-start', index: 0, blockType: 'reasoning' },
+      { type: 'text-delta', index: 0, text: 'x' },
+    ], /got reasoning/],
+    [[{ type: 'block-end', index: 0, block: { type: 'text', text: '' } }], /has no open block/],
+    [[
+      { type: 'block-start', index: 0, blockType: 'text' },
+      { type: 'block-end', index: 0, block: { type: 'reasoning', text: '' } },
+    ], /closes reasoning, expected text/],
+    [[
+      { type: 'usage', usage: { inputTokens: 1, outputTokens: 1 } },
+      { type: 'usage', usage: { inputTokens: 1, outputTokens: 1 } },
+    ], /usage more than once/],
+    [[{ type: 'block-start', index: 0, blockType: 'text' }, finish], /finished with 1 open block/],
+    [[finish, { type: 'usage', usage: { inputTokens: 1, outputTokens: 1 } }], /usage after terminal finish/],
+    [[], /ended without a terminal finish/],
+  ] as Array<[StreamChunk[], RegExp]>)('rejects malformed stream %#', async (chunks, message) => {
+    const ctx = await setup()
+    await expect(consume(ctx, chunks)).rejects.toThrow(message)
+  })
+
+  it('preserves provider exceptions without inventing a missing-finish failure', async () => {
+    const ctx = await setup()
+    const stream = ctx.waterfall(ctx as never, 'llm/stream', options, async function* () {
+      throw new Error('provider failed')
+    })
+    await expect((async () => {
+      for await (const _chunk of stream) { /* consume */ }
+    })()).rejects.toThrow('provider failed')
+  })
+})

packages/llm/llm/tests/service.spec.ts

@@ -60,6 +60,7 @@ class CatalogAdapter extends ScriptedAdapter {
 const SCRIPT: StreamChunk[] = [
   { type: 'block-start', index: 0, blockType: 'text' },
   { type: 'text-delta', index: 0, text: 'hi' },
+  { type: 'block-end', index: 0, block: { type: 'text', text: 'hi' } },
   { type: 'finish', reason: { kind: 'stop' } },
 ]
 
@@ -489,13 +490,14 @@ describe('LlmService', () => {
       const inner = next()
       return (async function * () {
         yield { type: 'block-start', index: 99, blockType: 'text' } satisfies StreamChunk
+        yield { type: 'block-end', index: 99, block: { type: 'text', text: '' } } satisfies StreamChunk
         yield * inner
       })()
     })
 
     const chunks: StreamChunk[] = []
     for await (const chunk of ctx.llm.stream({ provider: 'test-model', model: 'dynamic-model', messages: [] })) chunks.push(chunk)
-    expect(chunks).toHaveLength(4)
+    expect(chunks).toHaveLength(6)
     expect(chunks[0]).toMatchObject({ index: 99 })
   })
 

packages/llm/token-meter/src/invariant.ts

@@ -1,28 +1,24 @@
-/** Package-owned runtime contract checks for `@deepseek-ai/dsh-token-meter`. @module @deepseek-ai/dsh-token-meter/invariant */
+/**
+ * Package-owned invariant companion for `@deepseek-ai/dsh-token-meter`.
+ * @module @deepseek-ai/dsh-token-meter/invariant
+ */
 
+/* jscpd:ignore-start */
 import type { Context } from 'cordis'
-import { observePluginInvariant, type InvariantInstaller } from '@deepseek-ai/dsh-invariants'
+import type { InvariantInstaller } from '@deepseek-ai/dsh-invariants'
 
 const PACKAGE_NAME = '@deepseek-ai/dsh-token-meter'
 
 /** Cordis companion plugin name. */
 export const name = 'token-meter-invariant'
-/** Services required before the companion can register. */
+/** Service required before the companion can reserve package ownership. */
 export const inject = ['invariants']
 
-/** Install checks for this package's active plugin fibers. */
-const install: InvariantInstaller = (ctx, fail) => {
-  observePluginInvariant(ctx, fail, {
-    name: 'TokenMeterService',
-    effects: [
-      'ctx.provide("tokenMeter")',
-      'ctx.on("session/event")',
-    ],
-    services: [
-      'tokenMeter',
-    ],
-  })
-}
+/**
+ * No runtime invariant: token estimates are per-call outputs and the private session cache is
+ * invalidated at its event mutation boundary; neither exposes an independent observation stream.
+ */
+const install: InvariantInstaller = () => {}
 
 /**
  * Register this package's invariant companion.
@@ -31,3 +27,4 @@ const install: InvariantInstaller = (ctx, fail) => {
  */
 export const apply = (ctx: Context): Promise<() => void> =>
   Promise.resolve(ctx.invariants.register(PACKAGE_NAME, install))
+/* jscpd:ignore-end */