📦 @goodandready/dsh-usage-guard

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⚡ The Root Problem: How Upstream Providers Poison Session History

In DeepSeek Harness, session projections aggregate cumulative token usage across four core buckets:

uncachedInputTokens: usage.inputTokens,        // No safety fallback in DSH core!
outputTokens:        usage.outputTokens,       // No safety fallback in DSH core!
cacheReadTokens:     usage.cacheReadTokens ?? 0,
cacheWriteTokens:    usage.cacheWriteTokens ?? 0,

While DSH core guards cacheReadTokens and cacheWriteTokens with ?? 0, it takes inputTokens and outputTokens as raw numbers without safety checks.

When third-party providers, local inference servers, custom proxy gateways, or community routers return non-standard payloads, missing fields, or NaN, standard JavaScript arithmetic (total += NaN) instantly converts the session's cumulative token sum into NaN.

Subsequently, DSH schema validation fatally rejects the entire session digest:

history unavailable for session "<session-id>": expected number, received NaN

Because session history in DSH is computed dynamically by replaying the event log, a single malformed token packet permanently bricks the entire conversation history from being opened ever again.

graph LR
    subgraph Malformed [Upstream Provider Stream]
        API[LLM Output Stream] -->|Returns prompt_tokens / NaN / null| Event[Session Event Chunk]
    end

    subgraph Unprotected [Without dsh-usage-guard]
        Event --> DSHMath[DSH Cumulative Arithmetic]
        DSHMath -->|total += NaN| Poison[🚨 Cumulative Total becomes NaN]
        Poison --> SchemaFail[Schema Validation Rejection]
        SchemaFail --> DeadHistory[💥 Session History Permanently Unreadable]
    end

    subgraph Guarded [With dsh-usage-guard Active]
        Event --> Patch[sessionProjections Interceptor]
        Patch --> AliasCheck{Alias Borrowing Layer}
        AliasCheck -->|Maps prompt_tokens -> inputTokens| Restored[Restored Number]
        AliasCheck -->|If missing / NaN| ZeroFallback[Safe 0 Fallback]
        Restored --> SafeMath[Clean Arithmetic Execution]
        ZeroFallback --> SafeMath
        SafeMath --> ValidHistory[✅ 100% Intact & Recovered Session History]
    end

    style Malformed fill:#1e1e2e,stroke:#89b4fa,stroke-width:2px,color:#cdd6f4
    style Unprotected fill:#311b1b,stroke:#f38ba8,stroke-width:2px,color:#cdd6f4
    style Guarded fill:#181825,stroke:#a6e3a1,stroke-width:2px,color:#cdd6f4

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✨ Key Features & Architectural Defense

1. Instant Replay Recovery for Existing Corrupted Sessions

The plugin does not alter or rewrite log files on disk. Instead, it hooks the projection fold at runtime. Because session replay passes through this exact interception point, all previously broken or locked sessions are instantly restored and readable immediately upon installing the plugin.

2. Comprehensive Alias Borrowing Lexicon (borrowed)

Before substituting zero, dsh-usage-guard scans an extensive dictionary of industry-standard field aliases:

| Target DSH Field | Recognized Vendor Aliases | |---|---| | inputTokens | input_tokens, input, promptTokens, prompt_tokens, promptTokenCount, prompt_eval_count | | outputTokens | output_tokens, output, completionTokens, completion_tokens, candidatesTokenCount, eval_count | | cacheReadTokens | cache_read_tokens, cachedTokens, cached_tokens, cache_read_input_tokens, cachedContentTokenCount, prompt_tokens_details.cached_tokens | | cacheWriteTokens | cache_write_tokens, cacheCreationTokens, cache_creation_input_tokens |

3. Finite Non-Negative Integer Soundness Validation (sound)

Strictly validates typeof value === 'number' && Number.isFinite(value) && value >= 0 && Number.isInteger(value) to filter out NaN, Infinity, null, undefined, negative error codes (e.g. -1), non-integer floats, and malformed strings.

4. Safe Zero Fallback & Float Rounding (repaired)

If a counter cannot be resolved from aliases, it is safely initialized to 0. Fractional tokens or decimal strings are safely rounded via Math.round(), strictly satisfying the core DSH contract z.number().int().nonnegative().

5. In-Memory Registry Monkey-Patching (lib/patch.js)

• Pre-existing Projections: Wraps all .apply methods currently registered in sessionProjections.registrations while preserving full this context.
• Late-Binding Projections: Traps future projection registrations via map.set wrapping, guaranteeing 100% coverage regardless of plugin loading order.
• Universal Projection Protection: Protects not only token counters, but also context pressure calculators and busy-state analyzers.
• Zero Performance Overhead: Uses shallow event cloning only along the usage path, while a high-performance WeakMap cache ensures single execution across all 10–15 parallel DSH projections.

6. Deduplicated Diagnostic Reporting (told)

Logs informative diagnostic warnings naming the exact session, turn, step, raw payload, and recovery action (e.g. inputTokens borrowed from alias vs inputTokens zeroed). Incidents are deduplicated in memory so logs are not flooded during replays, and the cache is bounded to 1,000 entries with O(1) FIFO eviction.

7. Native Web UI Settings Card (lib/client.js)

• Mounts into the native Settings tab under Settings → Plugins → Plugin Settings (settings.plugin.item) with real-time status badge, auto-dismissing save feedback, and full localization.

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🚀 Changed in v0.1.5

• Strict settings.plugin.item Registration (#3): Completely removed the deprecated fallback registration into settings.section. In compliance with DSH Plugin Authoring guidelines, settings are rendered exclusively in the "Settings → Plugins" tab (settings.plugin.item) with key dsh-usage-guard without cluttering the global sidebar.
• Refined Client Architecture: Cleaned up the browser bundle to register strictly one slot entry with zero runtime fallback delays.

🚀 Changed in v0.1.4

• Style Isolation with data-dsh-plugin: Dynamic <style> element is explicitly tagged with data-dsh-plugin="dsh-usage-guard", preventing style purging during neighbor plugin reloads or HMR.
• Direct Slot Registration: Replaced broken invocation pattern with standard ctx.slots.register('settings.plugin.item', ...).
• Canonical Localization Standard: Streamlined client registration to strictly register the canonical English locale dictionary, delegating localized user interfaces to DSH translation plugins.
• Safe Configuration Loading & English Diagnostics: Protected Config() initialization with try...catch and migrated diagnostic log messages to English.

🚀 Changed in v0.1.3

• Fractional Token Protection (Floats & Decimals):
  • DeepSeek Harness @deepseek-ai/dsh-token-meter projection schema enforces strict integers (z.number().int().nonnegative()). Fractional tokens (e.g. 42.5 or "1540.2" produced by routing proxies or weighted estimators) previously broke Zod schema validation.
  • sound() now strictly validates Number.isInteger(value).
  • Floating-point numbers and decimal strings are now safely rounded to non-negative integers via Math.round() (42.6 $\rightarrow$ 43), protecting session history from schema rejections.
• High-Performance WeakMap Cache (guard):
  • DSH executes 10–15 parallel projection folds for every session event.
  • A WeakMap<event, guardedEvent> cache sanitizes each incoming event exactly once on the first projection, returning the cached normalized reference to all subsequent projections in $O(1)$ without re-parsing or memory leak risks.
• Strict O(1) FIFO Eviction in told Warning Cache:
  • Replaced bulk told.clear() with individual oldest key eviction told.delete(oldest) at 1,000 entries, maintaining continuous deduplication without sudden re-logging storms.
• Web UI Settings Card UX & A11y Polish:
  • Save status confirmation ("Saved") now automatically auto-dismisses after 3 seconds and clears immediately upon toggle adjustment.
  • Added reactive external synchronization with server-side config changes when the user has no uncommitted draft.
  • Enhanced accessibility: connected inputs to labels via htmlFor/id and tagged the chevron icon with aria-hidden="true".

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🚀 Changed in v0.1.2

• Native Web UI Settings Card (settings.plugin.item):
  • Added frontend client module lib/client.js registering a native configuration card under Settings → Plugins → Plugin Settings bound to namespace dsh-usage-guard (Issue #2).
  • Interactive toggles for repair (automatic token counter repair) and report (diagnostic warning console logging).
  • Real-time status badge in card header (ACTIVE when auto-repair is enabled, REPORT ONLY when passive audit is selected).
  • Strict compliance with DSH native theme CSS variables, core chevron icon IconChevronDownOutline14, 12px border radius, and aria-expanded accessibility.
  • Complete trilingual localization for English, Russian, and Chinese (en, ru, zh).
  • Graceful fallback slot settings.section for legacy core versions without the plugin settings tab.
• Design Contract:
  • Added official UI design contract in docs/design/DESIGN.md complying with project-design-contract and dsh-ui-design.

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🚀 Changed in v0.1.1

• Negative Number Protection (nonnegative): In v0.1.0, negative counters like -1 (sometimes returned by proxy gateways during rate limits or faults) passed finite-number checks and crashed DSH schema validation (z.number().int().nonnegative()). In v0.1.1, sound() strictly requires value >= 0. Any negative number is treated as corrupted and safely zeroed out.
• Safe Coercion of Stringified Numbers: If an upstream provider delivers valid token counts formatted as strings (e.g. inputTokens: "1540"), v0.1.1 coerces them into true numbers rather than resetting them to zero.
• Expanded Ecosystem Aliases:
  • Google Gemini API: added promptTokenCount, candidatesTokenCount, and cachedContentTokenCount.
  • Ollama native API: added prompt_eval_count and eval_count.
  • OpenAI prompt caching: added nested resolution of prompt_tokens_details.cached_tokens.
• Preservation of this Context in Projections: In lib/patch.js, wrapApply now dispatches via original.call(this, state, guard(event)), ensuring complete compatibility with class-based projection handlers.
• Crash-Proof Diagnostic Logging: In complaint(), object serialization is now safely protected with try...catch against circular structures and BigInt values.
• Session-Aware Deduplication & Memory Bound: Warning deduplication now incorporates sessionId to avoid cross-session warning suppression. told cache size is bounded to 1,000 entries to prevent memory growth in long-running processes.

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📦 Quick Installation

dsh plugin --profile web add @goodandready/dsh-usage-guard

[!IMPORTANT] Restart DSH Web UI after installation (systemctl --user restart dsh-web) to activate protection and instantly revive any previously locked sessions.

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⚙️ Configuration Reference (settings.yaml / Web UI)

dsh-usage-guard:
  repair: true
  report: true

| Parameter | Type | Default | Description | |---|---|---|---| | repair | boolean | true | Replace missing or non-numeric token counters with zero before arithmetic accumulation | | report | boolean | true | Log diagnostic warning lines naming turn, step, and raw sample when damaged metrics arrive |

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📄 License

MIT © GooDAnDReaDY