bulla 0.7.1

Witness kernel for agent tool compositions — diagnose, attest, seal

bulla

Witness kernel for agent tool compositions — diagnose, attest, seal. Finds semantic blind spots that bilateral verification cannot reach and recommends bridge annotations to eliminate them.

Zero heavy dependencies. Only requires PyYAML. No numpy, no scipy, no LLM calls. Installs in under a second.

Naming: Bulla is the protocol and tool. SEAM is the underlying theory. Glyph is the company.

Install

pip install bulla

Quick start

Run the built-in examples to see output immediately:

bulla diagnose --examples

Diagnose your own composition:

bulla diagnose my_pipeline.yaml

Library API

BullaGuard is the primary programmatic interface. Use it to embed coherence analysis in any Python application, agent framework, or CI pipeline.

from bulla import BullaGuard, BullaCheckError

# Path A: From raw tool definitions (the framework integration path)
guard = BullaGuard.from_tools({
    "invoice_parser": {
        "fields": ["total_amount", "due_date", "line_items", "currency"],
        "conventions": {"amount_unit": "dollars", "date_format": "ISO-8601"},
    },
    "settlement_engine": {
        "fields": ["amount", "settlement_date", "ledger_entry"],
        "conventions": {"amount_unit": "cents"},
    },
}, edges=[("invoice_parser", "settlement_engine")])

# Path B: From MCP manifest JSON
guard = BullaGuard.from_mcp_manifest("manifest.json")

# Path C: From YAML composition (the v0.1 path)
guard = BullaGuard.from_composition("pipeline.yaml")

# Path D: From a live MCP server via stdio
guard = BullaGuard.from_mcp_server("python my_server.py")

# Diagnose
diag = guard.diagnose()
diag.coherence_fee         # int
diag.blind_spots           # list[BlindSpot]
diag.bridges               # list[Bridge]

# Check (raises BullaCheckError if thresholds exceeded)
guard.check(max_blind_spots=0, max_unbridged=0)

# Export
guard.to_yaml("pipeline.yaml")   # save for CI
guard.to_json()                   # JSON string with version + hash
guard.to_sarif()                  # SARIF string

Framework integration example

A LangChain integration becomes:

from bulla import BullaGuard

class BullaCoherenceCallback(BaseCallbackHandler):
    def on_chain_start(self, serialized, inputs, **kwargs):
        tools = extract_tools_from_chain(serialized)
        guard = BullaGuard.from_tools(tools)
        diag = guard.diagnose()
        if diag.coherence_fee > 0:
            warnings.warn(f"Composition has {len(diag.blind_spots)} blind spots")

What it does

When tools in a pipeline share implicit conventions (date formats, unit scales, encoding schemes), some of those conventions may be invisible to bilateral verification -- each pair of tools looks correct in isolation, but the pipeline as a whole can silently produce wrong results.

bulla computes the coherence fee: the number of independent semantic dimensions that fall through the cracks of pairwise checks. For each blind spot, it recommends a bridge -- a specific field to expose in the tool's observable schema.

  Financial Analysis Pipeline
  ═══════════════════════════

  Topology: 3 tools, 3 edges, beta_1 = 1

  Blind spots (2):
    [1] day_conv_match (data_provider -> financial_analysis)
        day_convention hidden on both sides
    [2] metric_type_match (financial_analysis -> portfolio_verification)
        risk_metric hidden on both sides

  Recommended bridges:
    [1] Add 'day_convention' to F(data_provider) and F(financial_analysis)
    [2] Add 'risk_metric' to F(financial_analysis) and F(portfolio_verification)

  After bridging: fee = 0

Composition format

Compositions are YAML files that describe your tool pipeline. See composition-schema.json for the full schema.

name: My Pipeline

tools:
  tool_a:
    internal_state: [field_x, field_y, hidden_z]
    observable_schema: [field_x, field_y]

  tool_b:
    internal_state: [field_x, hidden_z]
    observable_schema: [field_x]

edges:
  - from: tool_a
    to: tool_b
    dimensions:
      - name: x_match
        from_field: field_x
        to_field: field_x
      - name: z_match
        from_field: hidden_z
        to_field: hidden_z

• internal_state: All semantic dimensions the tool operates on internally (the full stalk S(v)).
• observable_schema: Dimensions visible in the tool's API (the observable sub-sheaf F(v)). Must be a subset of internal_state.
• edges: Bilateral interfaces between tools. Each dimension names a shared convention.

A dimension is a blind spot when from_field or to_field is in internal_state but not in observable_schema of the respective tool.

Commands

bulla diagnose

Diagnose compositions and report blind spots, bridges, and the coherence fee.

bulla diagnose pipeline.yaml                    # text output
bulla diagnose --format json pipeline.yaml      # JSON with version + SHA-256
bulla diagnose --format sarif pipeline.yaml     # SARIF for GitHub code scanning
bulla diagnose --examples                       # run on bundled examples

bulla check

CI/CD gate. Exits with code 1 if any composition exceeds the specified thresholds.

bulla check pipeline.yaml                                   # default: --max-blind-spots 0 --max-unbridged 0
bulla check --max-blind-spots 2 compositions/               # allow up to 2 blind spots
bulla check --format sarif compositions/ > results.sarif    # SARIF for GitHub Actions

bulla scan

Scan live MCP servers via stdio. Zero configuration — no YAML required.

bulla scan "python my_server.py"                             # single server
bulla scan "python server_a.py" "python server_b.py"         # multi-server composition
bulla scan "python server.py" -o pipeline.yaml               # save for CI
bulla scan "python server.py" --format json                  # JSON diagnostic

The scanner spawns each server as a subprocess, performs the MCP initialize handshake, queries tools/list, and auto-generates a composition using the heuristic dimension classifier. No MCP SDK dependency.

bulla manifest

Generate or validate Bulla Manifest files.

bulla manifest --from-json tools.json -o manifest.yaml       # from MCP manifest JSON
bulla manifest --from-server "python server.py"              # from live MCP server
bulla manifest --validate manifest.yaml                      # validate against spec

bulla init

Interactive wizard to generate a composition YAML.

bulla init
bulla init -o my_pipeline.yaml

bulla infer

Infer a proto-composition from an MCP manifest JSON.

bulla infer manifest.json                # stdout
bulla infer manifest.json -o proto.yaml  # save to file

bulla --version

Print the installed version.

Bulla Manifest Specification

The Bulla Manifest Spec v0.1 defines a per-tool convention declaration format. Each manifest declares what semantic conventions a single tool assumes (e.g. "amounts are in dollars", "dates are ISO-8601").

See the spec, JSON Schema, and the built-in taxonomy of 10 convention dimensions.

CI integration

GitHub Actions with SARIF

name: bulla
on: [push, pull_request]
jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-python@v5
        with:
          python-version: "3.11"
      - run: pip install bulla
      - run: bulla check --format sarif compositions/ > bulla.sarif
      - uses: github/codeql-action/upload-sarif@v3
        if: always()
        with:
          sarif_file: bulla.sarif

This uploads results to GitHub's code scanning tab, where blind spots appear as annotations on pull requests.

Simple pass/fail

      - run: pip install bulla
      - run: bulla check compositions/

Output formats

Format	Flag	Use case
Text	--format text (default)	Developer terminal
JSON	--format json	Orchestrator integration, includes version + SHA-256
SARIF	--format sarif	GitHub code scanning, VS Code SARIF viewer

How it works

bulla builds a discrete coboundary operator (delta-0) from C^0 (tool dimensions) to C^1 (edge dimensions) for both the observable sheaf F and the full sheaf S. The coherence fee is:

fee = H^1(F_obs) - H^1(F_full)
    = (dim C^1 - rank delta_obs) - (dim C^1 - rank delta_full)
    = rank delta_full - rank delta_obs

Each unit of fee corresponds to an independent semantic dimension that bilateral verification cannot detect. Bridging (exposing hidden fields in the observable schema) increases rank(delta_obs) until it matches rank(delta_full).

The rank computation uses exact arithmetic (Python's fractions.Fraction module) via Gaussian elimination -- no floating-point tolerance, no numpy dependency.

License

MIT