---
id: PLN-0010
ticket: generic-memory-bank-slot-contract
title: PR/Plan - Asset Manager Bank Telemetry Slot Contract
status: open
created: 2026-04-10
completed:
tags: [runtime, asset, memory-bank, slots, host, telemetry]
---

## Objective

Implement the `DEC-0012` bank telemetry contract so `AssetManager` exposes slot-based bank summaries using canonical bank names `GLYPH` and `SOUND`, while host overlay and certification consume slot-based limits instead of byte-based bank metrics.

## Background

`DEC-0012` locked the bank telemetry contract around a simple slot-first structure:

```rust
pub struct BankTelemetry {
    pub bank_type: BankType,
    pub used_slots: usize,
    pub total_slots: usize,
}
```

This replaces the old bank telemetry path that relied on byte-oriented structures and presentation aliases. The implementation must remove `BankPolicy` and `BankStats` from the exposed bank telemetry contract path, move visible bank summaries to `AssetManager`, and migrate certification rules from byte-based thresholds to slot-based thresholds.

## Scope

### Included
- Add a visible slot-based `BankTelemetry` contract owned by `AssetManager`.
- Remove `BankStats` from the public bank telemetry contract path.
- Remove `BankPolicy` from the bank telemetry contract path and refactor internal code accordingly.
- Update bridge/consumer APIs so bank summaries come from `AssetManager` slot telemetry.
- Migrate certification from `max_gfx_bytes` / `max_audio_bytes` to slot-based limits for `GLYPH` and `SOUND`.
- Update host overlay to iterate `AssetManager` bank telemetry using canonical `GLYPH` and `SOUND` labels.
- Update specs/docs affected by the contract change.

### Excluded
- Adding new bank kinds beyond the currently supported `GLYPH` and `SOUND`.
- Reworking unrelated asset load/commit semantics.
- Redesigning generic slot-detail payloads beyond the accepted summary shape unless implementation requires a narrowly scoped helper.

## Execution Steps

### Step 1 - Introduce `BankTelemetry` in the exposed asset contract

**What:**
Define the new slot-based summary type and make it the canonical visible representation of bank telemetry.

**How:**
Add `BankTelemetry` to the HAL asset domain and ensure canonical naming uses `GLYPH` and `SOUND`. Remove or deprecate exposed `BankStats` paths that conflict with the new contract.

**File(s):**
- `crates/console/prometeu-hal/src/asset.rs`
- `crates/console/prometeu-hal/src/asset_bridge.rs`

### Step 2 - Make `AssetManager` expose bank telemetry directly

**What:**
Implement `AssetManager` support for returning `Vec<BankTelemetry>` from live slot occupancy.

**How:**
Compute `used_slots` from current slot occupancy and `total_slots` from the fixed slot arrays for `GLYPH` and `SOUND`. Keep implementation simple and derive the summary directly from the installed slots. Refactor any existing public bank-info consumers away from byte-oriented APIs.

**File(s):**
- `crates/console/prometeu-drivers/src/asset.rs`
- `crates/console/prometeu-drivers/src/memory_banks.rs`

### Step 3 - Remove byte-based bank certification rules

**What:**
Replace byte-based certification limits for banks with slot-based limits.

**How:**
Remove `max_gfx_bytes` and `max_audio_bytes` from certification config and certifier checks. Introduce slot-based limits such as `max_glyph_slots_used` and `max_sound_slots_used`, and evaluate them against `BankTelemetry` summaries or equivalent slot-based data available at frame-end.

**File(s):**
- `crates/console/prometeu-hal/src/telemetry.rs`
- `crates/console/prometeu-system/src/virtual_machine_runtime/tick.rs`

### Step 4 - Update host overlay to consume slot telemetry

**What:**
Replace hardcoded bank presentation with iteration over `AssetManager` bank telemetry.

**How:**
Render one bar per bank using `bank_type`, `used_slots`, and `total_slots`. Use canonical labels `GLYPH` and `SOUND`, and remove any byte-based bank presentation from the overlay.

**File(s):**
- `crates/host/prometeu-host-desktop-winit/src/overlay.rs`
- Any host-side adapter/helper used to access asset telemetry

### Step 5 - Remove obsolete structures from the contract path

**What:**
Eliminate `BankPolicy` and `BankStats` from the exposed bank telemetry path.

**How:**
Refactor code so the new slot-based path is the only public contract. If internal implementation helpers must remain temporarily during migration, keep them private and make sure no consumer depends on them as contract.

**File(s):**
- `crates/console/prometeu-drivers/src/asset.rs`
- `crates/console/prometeu-hal/src/asset.rs`
- Related callers revealed during implementation

### Step 6 - Update normative documentation

**What:**
Align specifications with the new slot-based bank telemetry contract.

**How:**
Update relevant runtime documentation to describe bank occupancy in terms of `GLYPH` and `SOUND` slot usage, and remove outdated references to byte-based bank telemetry where they were treated as visible contract.

**File(s):**
- `docs/specs/runtime/10-debug-inspection-and-profiling.md`
- `docs/specs/runtime/15-asset-management.md`
- Any additional touched runtime spec chapter

## Test Requirements

### Unit Tests
- `AssetManager` reports correct `BankTelemetry` for empty and occupied `GLYPH` / `SOUND` slots.
- Certification slot limits trigger correctly for `GLYPH` and `SOUND`.
- Overlay rendering accepts generic bank telemetry iteration.

### Integration Tests
- `cargo check` for affected HAL, drivers, system, and host crates.
- Focused tests for asset bank telemetry and certification migration.

### Manual Verification
- Run the desktop host and confirm banks appear as `GLYPH` and `SOUND`.
- Confirm bank bars track occupied slots instead of bytes.
- Confirm certification behavior still reports bank pressure using slot limits.

## Acceptance Criteria

- [ ] `AssetManager` exposes a visible `BankTelemetry` summary with `bank_type`, `used_slots`, and `total_slots`.
- [ ] Canonical bank names in the new contract are `GLYPH` and `SOUND`.
- [ ] Byte-based bank certification limits are removed and replaced by slot-based limits.
- [ ] Host overlay renders bank occupancy from generic slot telemetry rather than byte-oriented hardcoded bank logic.
- [ ] `BankPolicy` and `BankStats` are no longer part of the exposed bank telemetry contract path.

## Dependencies

- `DEC-0012` accepted and unchanged.

## Risks

- Removing byte-based bank paths may have wider ripple effects than expected if old APIs are reused outside the overlay.
- The line between “removed from contract path” and “removed completely from implementation” must stay explicit during refactor to avoid accidental partial migration.
- Certification migration must stay synchronized with telemetry migration or the host and certifier will diverge semantically.