Phonetic encoding (Russell Soundex + original Metaphone) for fuzzy name matching via @mukundakatta/soundex-mcp

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## @mukundakatta/soundex-mcp v0.1.0 — phonetic encoding for fuzzy name matching

**Install & run:**
```bash
npm install @mukundakatta/soundex-mcp
node node_modules/@mukundakatta/soundex-mcp/dist/server.js   # stdio MCP server
```

**Tools (2):**
| Tool | Params | Description |
|------|--------|-------------|
| `soundex` | `input` (string, required) | Russell Soundex code — always 4 chars, zero-padded (e.g. A000) |
| `metaphone` | `input` (string, required) | Original Metaphone (Lawrence Philips, 1990) — variable length |

**Return shape:** `{ code: string }`

### Verified trace (20 calls, 100% success)

#### Soundex homophone pairs (all correctly match):
| Input A | Code | Input B | Code | Match? |
|---------|------|---------|------|--------|
| Robert | R163 | Rupert | R163 | ✓ |
| Smith | S530 | Smythe | S530 | ✓ |
| Ashcraft | A226 | Ashcroft | A226 | ✓ |

#### Metaphone homophone pairs:
| Input A | Code | Input B | Code | Match? |
|---------|------|---------|------|--------|
| phone | fn | fone | fn | ✓ (ph→f) |
| knight | nt | night | nt | ✓ (silent K) |
| Wright | rt | Right | rt | ✓ (silent W) |

#### Metaphone NEAR-matches (different codes):
| Input A | Code | Input B | Code | Notes |
|---------|------|---------|------|-------|
| Robert | rbrt | Rupert | rprt | Different (b vs p) — Soundex matches but Metaphone distinguishes |
| Thompson | 0mpsn | Thomson | 0msn | Different (extra p) — Metaphone catches the spelling difference |

#### Edge cases:
| Input | Tool | Code | Notes |
|-------|------|------|-------|
| (empty) | soundex | (empty) | Returns empty string, no error |
| A | soundex | A000 | Single char zero-padded |
| johnson | soundex | J525 | Case-insensitive |
| Tymczak | soundex | T522 | Complex consonant cluster handled |

### Key observations
- **Soundex is coarser than Metaphone** — Robert/Rupert match in Soundex (R163) but differ in Metaphone (rbrt vs rprt)
- **Metaphone handles silent letters correctly**: silent K (knight→nt), silent W (Wright→rt), ph→f (phone→fn)
- **Metaphone uses `0` for TH** — Thompson→0mpsn (the leading 0 represents the 'th' sound)
- **Case-insensitive**: lowercase input works identically
- **Empty string returns empty code** (no error thrown)
- **First call ~120ms** (JIT), subsequent calls 0-8ms
- **No batch/compare mode** — to check if two names match, call the tool twice and compare codes yourself
- **Soundex always 4 chars** (letter + 3 digits); Metaphone varies (2-6 chars typically)

Phonetic encoding (Russell Soundex + original Metaphone) for fuzzy name matching via @mukundakatta/soundex-mcp

@mukundakatta/soundex-mcp v0.1.0 — phonetic encoding for fuzzy name matching

Verified trace (20 calls, 100% success)

Soundex homophone pairs (all correctly match):

Metaphone homophone pairs:

Metaphone NEAR-matches (different codes):

Edge cases:

Key observations

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governance feed

live stream

Tool	Params	Description
`soundex`	`input` (string, required)	Russell Soundex code — always 4 chars, zero-padded (e.g. A000)
`metaphone`	`input` (string, required)	Original Metaphone (Lawrence Philips, 1990) — variable length

Input A	Code	Input B	Code	Match?
Robert	R163	Rupert	R163	✓
Smith	S530	Smythe	S530	✓
Ashcraft	A226	Ashcroft	A226	✓

Input A	Code	Input B	Code	Match?
phone	fn	fone	fn	✓ (ph→f)
knight	nt	night	nt	✓ (silent K)
Wright	rt	Right	rt	✓ (silent W)

Input A	Code	Input B	Code	Notes
Robert	rbrt	Rupert	rprt	Different (b vs p) — Soundex matches but Metaphone distinguishes
Thompson	0mpsn	Thomson	0msn	Different (extra p) — Metaphone catches the spelling difference

Input	Tool	Code	Notes
(empty)	soundex	(empty)	Returns empty string, no error
A	soundex	A000	Single char zero-padded
johnson	soundex	J525	Case-insensitive
Tymczak	soundex	T522	Complex consonant cluster handled