five-mcp
MCP server for the FIVE Persona Engine — an LLM persona constraint engine that generates structured JSON constraints to eliminate persona drift. Instead of describing personality in words (which LLMs interpret differently each turn), FIVE defines behavioral parameters the LLM executes as a recipe. See how it works →
Measured: with the constraint JSON + free harness, the demo character survived a 120-turn pressure test with zero persona breaks (plain prompt: 8 breaks; JSON alone: 1). Numbers, transcripts and scripts →
Free — no API key, no account.
Quick Start
Install
pip install five-mcp
Use with Claude Desktop
Add to your claude_desktop_config.json:
{
"mcpServers": {
"five-character-engine": {
"command": "five-mcp"
}
}
}
That's it — no environment variables needed.
Use with other MCP clients
Any MCP-compatible client can connect via stdio transport:
five-mcp
Tool: generate
Generates persona constraints via the FIVE engine.
Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
character_name |
string | Yes | Name of the character |
q1 – q4 |
A / B / C / D | Yes | Personality axis choices |
s1 – s4 |
1–5 | No | Style sliders (default: 3) |
free_text |
string | No | Free-form description |
Response
{
"status": "ok",
"constraint": { "..." }
}
Rate limits
The API is free. To keep it available to everyone, a light per-IP limit applies: 10 requests/min, 200 requests/day. The free host may cold-start, so the first call can take up to a minute.
Links
- API & Docs: fiveengine.dev
- GitHub: github.com/kiro0x/five-mcp
- Design philosophy & examples: five-character-engine README
- Measured evaluation (120-turn drift test): five-character-engine eval/
- Engine repo: github.com/kiro0x/five-character-engine
License
MIT
mcp-name: io.github.kiro0x/five-mcp
Download files
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.
Source Distribution
Built Distribution
Filter files by name, interpreter, ABI, and platform.
If you're not sure about the file name format, learn more about wheel file names.
Copy a direct link to the current filters
File details
Details for the file five_mcp-1.1.1.tar.gz.
File metadata
- Download URL: five_mcp-1.1.1.tar.gz
- Upload date:
- Size: 4.9 kB
- Tags: Source
- Uploaded using Trusted Publishing? Yes
- Uploaded via: twine/6.1.0 CPython/3.13.12
File hashes
| Algorithm | Hash digest | |
|---|---|---|
| SHA256 |
27687bc0b102fa5318ced2631711903f7819cc942bde55443bdf1ae2ca330e81
|
|
| MD5 |
69e41ff3b7b8126d6c240e24b13781e9
|
|
| BLAKE2b-256 |
c38567e777746a034d99e4b2309ed95c4da4fe074cadce24e6e8a3002eb69715
|
Provenance
The following attestation bundles were made for five_mcp-1.1.1.tar.gz:
Publisher:
publish.yml on kiro0x/five-mcp
-
Statement:
-
Statement type:
https://in-toto.io/Statement/v1 -
Predicate type:
https://docs.pypi.org/attestations/publish/v1 -
Subject name:
five_mcp-1.1.1.tar.gz -
Subject digest:
27687bc0b102fa5318ced2631711903f7819cc942bde55443bdf1ae2ca330e81 - Sigstore transparency entry: 2152637924
- Sigstore integration time:
-
Permalink:
kiro0x/five-mcp@ff4c78249e00c65a5f90cd283b113c06b914e747 -
Branch / Tag:
refs/heads/main - Owner: https://github.com/kiro0x
-
Access:
public
-
Token Issuer:
https://token.actions.githubusercontent.com -
Runner Environment:
github-hosted -
Publication workflow:
publish.yml@ff4c78249e00c65a5f90cd283b113c06b914e747 -
Trigger Event:
workflow_dispatch
-
Statement type:
File details
Details for the file five_mcp-1.1.1-py3-none-any.whl.
File metadata
- Download URL: five_mcp-1.1.1-py3-none-any.whl
- Upload date:
- Size: 5.2 kB
- Tags: Python 3
- Uploaded using Trusted Publishing? Yes
- Uploaded via: twine/6.1.0 CPython/3.13.12
File hashes
| Algorithm | Hash digest | |
|---|---|---|
| SHA256 |
0a4147b4998bd1fbf4c5a8de6b1df82d24b9fa1d8c5ba7c4fea2ff1855b3ea69
|
|
| MD5 |
afd73c3e13687dc79e1346708ba1fbc3
|
|
| BLAKE2b-256 |
e3efd26f4367afacf4c6ddec5739982c82e76fcadf5abe87c0efb8a41ed713b7
|
Provenance
The following attestation bundles were made for five_mcp-1.1.1-py3-none-any.whl:
Publisher:
publish.yml on kiro0x/five-mcp
-
Statement:
-
Statement type:
https://in-toto.io/Statement/v1 -
Predicate type:
https://docs.pypi.org/attestations/publish/v1 -
Subject name:
five_mcp-1.1.1-py3-none-any.whl -
Subject digest:
0a4147b4998bd1fbf4c5a8de6b1df82d24b9fa1d8c5ba7c4fea2ff1855b3ea69 - Sigstore transparency entry: 2152637956
- Sigstore integration time:
-
Permalink:
kiro0x/five-mcp@ff4c78249e00c65a5f90cd283b113c06b914e747 -
Branch / Tag:
refs/heads/main - Owner: https://github.com/kiro0x
-
Access:
public
-
Token Issuer:
https://token.actions.githubusercontent.com -
Runner Environment:
github-hosted -
Publication workflow:
publish.yml@ff4c78249e00c65a5f90cd283b113c06b914e747 -
Trigger Event:
workflow_dispatch
-
Statement type: