# Sprint 147 Plan: Parser/AST Adapter Interface and Multi-Language Baselines

## Context

With neutral core contracts defined, Sprint 147 introduces a stable adapter
interface for parser/AST providers and validates it with multiple languages.

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## Goals

1. Define adapter API boundaries for parser, AST mapping, and diagnostics
2. Implement at least two first-class adapters (C++ plus one non-C++)
3. Normalize adapter error surfaces and capability declarations
4. Ensure deterministic adapter selection and routing

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## Steps

### Step 1709: Parser/AST adapter interface schema (10 tests)
### Step 1710: Adapter registry and lifecycle model (10 tests)
### Step 1711: C++ adapter conformance harness model (10 tests)
### Step 1712: Non-C++ adapter conformance harness model (10 tests)
### Step 1713: `whetstone_list_language_adapters` MCP tool (8 tests)
### Step 1714: `whetstone_probe_language_adapter` MCP tool (8 tests)
### Step 1715: `whetstone_select_language_adapter` MCP tool (8 tests)
### Step 1716: Adapter health and conformance score model (8 tests)
### Step 1717: Multi-adapter compatibility report artifact (8 tests)
### Step 1718: Sprint 147 integration summary + regression (8 tests)

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## Architecture Gate

- Adapter interface must remain language-agnostic and versioned
- Adapter selection must be deterministic under identical inputs
- Conformance failures must include structured actionable diagnostics
- Max 600 lines per header