# Sprint 135 Plan: Deterministic MCP Execution Telemetry and Replay Packs

## Context

To debug wiring regressions, execution traces must be deterministic and compact.
Sprint 135 standardizes MCP execution telemetry with replay-ready packets.

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## Goals

1. Capture deterministic MCP execution telemetry per tool call
2. Normalize argument/result traces for replay and comparison
3. Build compact replay packs for cross-run debugging
4. Support low-context agent diagnosis of MCP regressions

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## Steps

### Step 1589: MCP execution event schema (10 tests)
### Step 1590: Argument/result canonicalizer model (10 tests)
### Step 1591: Deterministic replay pack composer (10 tests)
### Step 1592: Replay divergence comparator model (10 tests)
### Step 1593: `whetstone_capture_mcp_execution_trace` MCP tool (8 tests)
### Step 1594: `whetstone_export_mcp_replay_pack` MCP tool (8 tests)
### Step 1595: `whetstone_compare_mcp_replays` MCP tool (8 tests)
### Step 1596: Trace quality scorer model (8 tests)
### Step 1597: MCP replay diagnostics artifact (8 tests)
### Step 1598: Sprint 135 integration summary + regression (8 tests)

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## Architecture Gate

- Trace normalization must produce stable outputs
- Replay comparisons must return structured divergence packets
- Trace capture must preserve privacy and workspace scoping rules
- Max 600 lines per header