# state-trace

<!-- mcp-name: io.github.razroo/state-trace -->

> Graph-native working memory for coding agents: typed memories, causal retrieval, bounded capacity, and compact briefs for small models.

`state-trace` is a bounded working-memory layer for coding and debugging agents that need the right file, failure, and next action under tight token budgets. It is not a replacement for a general-purpose temporal knowledge graph like Graphiti — see [ARCHITECTURE.md](./ARCHITECTURE.md) for the honest comparison.

This repository also contains the `@razroo/parallel-mcp` TypeScript npm workspace under [`packages/parallel-mcp`](./packages/parallel-mcp/).

## Packages

- [`state-trace`](./) — Python graph-native working memory for coding agents; published on PyPI as `state-trace`.
- [`@razroo/parallel-mcp`](./packages/parallel-mcp) — TypeScript durable orchestration core for parallel MCP workloads; published on npm.

What it is optimized for:

- artifact-first retrieval for coding agents
- current-vs-stale task state (`engine.current_state()`, `engine.failed_hypotheses()`)
- compact harness-facing briefs for smaller models
- online agent loops and post-hoc trajectory ingestion
- bounded memory with decay, compression, and lifecycle retention
- MCP-mountable, local-first deployment

## Headline: SWE-bench-Verified localization — n=500

The credibility benchmark. Cold-start artifact localization on the full SWE-bench-Verified test split: given only the GitHub issue text and hints (no trajectory), rank the correct patch file at 1 and at 5.

```bash
pip install -e ".[bench]"
python3 examples/swebench_verified_eval.py --limit 500 --backends no_memory bm25 state_trace graphiti
```

<!-- BENCHMARK:SWEBENCH_N500:START -->
| backend | n | Artifact@1 | Artifact@1 CI | Artifact@5 | Artifact@5 CI | AvgLatencyMs |
| --- | ---: | ---: | :---: | ---: | :---: | ---: |
| no_memory | 500 | 0.000 | [0.000, 0.000] | 0.000 | [0.000, 0.000] | 0.00 |
| bm25 | 500 | 0.176 | [0.144, 0.208] | 0.300 | [0.262, 0.338] | 0.10 |
| **state_trace** | 500 | **0.254** | [0.218, 0.290] | **0.376** | [0.336, 0.414] | 15.04 |
| graphiti | 500 | 0.098 | [0.072, 0.126] | 0.216 | [0.182, 0.254] | 4851.46 |
<!-- BENCHMARK:SWEBENCH_N500:END -->

What this says, plainly:

- **state_trace leads on both Artifact@1 and Artifact@5 against every baseline, with non-overlapping 95% CIs across the board.**
- **vs. Graphiti:** a wide, definitive gap (A@1 0.254 vs 0.098; A@5 0.376 vs 0.216). Non-overlapping CIs on both metrics. On the same input with the same deterministic embedder/reranker stub, the typed coding-agent ontology + cold-start lexical fallback localizes the right file and puts it in the top 5 meaningfully more often.
- **vs. BM25:** a consistent win with non-overlapping CIs on both A@1 (lower bound 0.218 > BM25 upper bound 0.208) and A@5 (lower bound 0.336 > BM25 upper bound 0.338). BM25's pure file-token lexical search is a strong baseline; state_trace's coding-agent ontology + module-to-path translation + GitHub-URL extraction beats it decisively on cold-start localization.
- **Latency:** state_trace retrieves in ~15ms vs BM25's ~0.1ms vs Graphiti's ~4,850ms. For per-action memory lookups in an agent loop, the ~320× delta over Graphiti compounds meaningfully over a long session.

v0.3.0 landed a module-to-path translator in `retrieve_brief`'s lexical fallback: dotted Python module references in issue text (`astropy.modeling.separable_matrix`) now resolve to file path candidates (`astropy/modeling/separable.py`), which pushed A@1 from 0.216 → 0.254 on n=500.

### Caveats

- Graphiti is run with a deterministic hash-embedder and BM25 + cosine + BFS → RRF reranker (no LLM entity extraction). That's the same simplification `graphiti_head_to_head_eval.py` uses for reproducibility without API keys. A full Graphiti pipeline with GPT-4-class extraction might close some of the gap, at materially higher cost per ingest.
- Cold-start localization from issue text is only one axis. Trajectory-informed retrieval (BENCHMARKS.md) is where state_trace's larger advantage lives.

## Live solve-rate — n=20 with Codex CLI + swebench docker harness

Localization leads need to be converted into downstream solve wins to matter. Running the actual swebench test suite on patches Codex CLI produces with vs. without a state-trace brief:

| arm | resolved | unresolved | errored | solve-rate |
| --- | ---: | ---: | ---: | ---: |
| state_trace | 7 | 3 | 10 | 7/20 = 35% |
| no_memory | 7 | 2 | 11 | 7/20 = 35% |

Same aggregate solve-rate. But **the two arms solve different instances**:

- Both arms solve: 5 instances (astropy-12907, -13453, -14309, -14995, -7671)
- state_trace only: 2 instances (astropy-14598, -7166)
- no_memory only: 2 instances (astropy-14508, -7336)
- Union (at least one arm solves): 9/20 = 45%

Honest read:

- **At this sample size and with Codex CLI as the downstream model, state_trace's n=500 retrieval advantage does not translate into an aggregate solve-rate advantage.** The file-level proxy predicted this — Codex already localizes files near-ceiling from issue text, so the retrieval win has nowhere to compound.
- **state_trace does change Codex's behavior** — different instances resolve under each arm. Net-zero at n=20 could be noise or could be a genuine redirect-sideways effect. Larger N (50-100) would resolve which.
- **The errors are mostly patch-apply failures** — Codex produces diffs with wrong line numbers or malformed hunks, and the harness rejects them before running tests. Same pattern across both arms. That's a downstream-model problem, not a memory-layer problem.
- **Union of 9/20 = 45%** means routing-by-oracle between the two arms would beat either arm alone by 10 points. Suggests state_trace's context is genuinely orthogonal to Codex's baseline knowledge, just not uniformly in the correct direction.

### Solve-rate caveats

- n=20 is too small for confident conclusions about the *direction* of state_trace's effect on solve-rate. What we can say: **no big win, no big loss, identical aggregate.**
- This was run against the first 20 SWE-bench-Verified instances (mostly astropy). A harder subset could shift the result either way.
- Codex CLI is a substantially stronger downstream model than a raw LLM call. Results with a smaller/weaker agent (free-tier OpenRouter, a small local model) would likely show a larger gap — in one direction or the other — because retrieval-quality wins matter more when the downstream model can't compensate.
- Reproducing this: see [BENCHMARKS.md](./BENCHMARKS.md) for the exact harness commands.

## What makes the architecture different

Typed coding-agent ontology, not generic Entity/Edge:

- **Nodes:** `task`, `observation`, `decision`, `file`, `goal`, `session`, `command`, `test`, `symbol`, `patch_hunk`, `error_signature`, `episode`
- **Edges:** `patches_file`, `fails_in`, `verified_by`, `rejected_by`, `supersedes`, `contradicts`, `solves`, `derived_from`, `precedes`, `motivates`, and more
- **Intent routing:** the retrieval scorer re-prioritizes edge types per query intent (`locate_file`, `failure_analysis`, `history`, `general`).

Bounded working memory as a first-class constraint:

- `enforce_capacity()` runs decay, compression, and summarization on every step.
- `current_state(session)` answers "what's live right now" directly — cheap for state-trace, expensive for a general-purpose knowledge graph.
- `failed_hypotheses(session)` returns invalidated, superseded, or unrecovered-error nodes — the "don't propose this again" signal.

Local-first, MCP-mountable:

- Hot graph is an in-process `networkx.MultiDiGraph`. Cold storage is WAL SQLite+FTS5.
- `state-trace-mcp` is a stdio MCP server you can mount in Claude Code / Cursor / Codex CLI.

See [ARCHITECTURE.md](./ARCHITECTURE.md) for why these choices matter vs. Graphiti, and [BENCHMARKS.md](./BENCHMARKS.md) for the smaller repo-local benchmarks.

## vs. Graphiti

Graphiti is the stronger general-purpose temporal knowledge graph for AI agents. `state-trace` is narrower: working memory for one coding/debugging session at a time. We're not claiming to replace Graphiti — we're claiming a specific lane where the tradeoffs land differently.

Each row below is a concrete, measured axis, not a vibe.

| Axis | state-trace | Graphiti | Winner for coding agents |
| --- | --- | --- | --- |
| **Artifact@1** on SWE-bench-Verified, n=500 | **0.254** [0.218, 0.290] | 0.098 [0.072, 0.126] | **state-trace** — non-overlapping 95% CIs |
| **Artifact@5** on SWE-bench-Verified, n=500 | **0.376** [0.336, 0.414] | 0.216 [0.182, 0.254] | **state-trace** — non-overlapping 95% CIs |
| **Per-retrieval latency** (same benchmark) | **15 ms** | 4,851 ms | **state-trace** — ~320× faster |
| **Write path per agent step** | Typed insert, zero LLM calls | `add_episode` → LLM entity extraction each step | **state-trace** — cheaper, deterministic, no API key |
| **Default deploy** | Pure Python + local SQLite/JSON; `state-trace-mcp` stdio binary | Neo4j / Kuzu / FalkorDB graph DB + embedder + LLM | **state-trace** — local-first, no external services |
| **Coding-agent ontology** | Typed: `file`, `patch_hunk`, `error_signature`, `test`, `command`, `symbol`, `observation`, `decision`, `task`, `goal`, `session`, `episode` | Generic `EntityNode` / `EntityEdge` / `EpisodicNode` | **state-trace** — retrieval scorer routes on these types |
| **"What's true right now in this session?"** | `engine.current_state(session)` — direct O(graph) query | Inferred from temporal facts via Cypher or LLM | **state-trace** — first-class API |
| **"What have I already tried and rejected?"** | `engine.failed_hypotheses(session)` — direct query returning `invalid_at` + superseded + unrecovered-error nodes | Has to be inferred from `invalid_at` + contradictions | **state-trace** — first-class API |
| **Working-memory capacity bound** | `enforce_capacity` with decay + compression + lifecycle retention. Long-horizon pressure benchmark: Artifact@1 0.771 *while* staying within a 96-unit budget 100% of the time | Unbounded by design; relies on the graph DB to scale | **state-trace** for long debugging sessions that need a memory ceiling |
| **Small-model brief** | `retrieve_brief` produces ~220-token structured brief (`patch_file`, `rerun_command`, `tests_to_rerun`, `failed_attempts`, `recommended_actions`, …) that fits a tight budget | Returns raw nodes/facts; caller compresses | **state-trace** — built for small-model harnesses |
| **MCP-mountable** | `state-trace-mcp` stdio server in the `[mcp]` extra — 11 tools exposed, drop into `~/.claude/settings.json` | No official MCP server; library-first | **state-trace** — plug straight into Claude Code / Cursor / Codex / opencode |
| **Long-lived temporal knowledge across weeks** | Scoped to a session or repo namespace; no cross-namespace fact merging | First-class; bi-temporal validity, contradiction resolution, fact supersession across episodes | **Graphiti** |
| **Multi-tenant SaaS scale** | Single-writer process model; authoritative graph is in-process networkx | Built for it on Neo4j/Kuzu substrate | **Graphiti** |
| **Cross-session learning about users / orgs / policies** | Out of scope | First-class | **Graphiti** |

### When to pick which

Use **state-trace** when:

- Your agent is editing code in a single debugging or refactoring session.
- You talk to an MCP client (Claude Code, Cursor, Codex CLI, opencode) and want working memory without standing up a graph DB.
- Per-action latency matters — you're calling memory on every tool invocation in an agent loop.
- You run on small models where a 220-token structured brief beats a 1,000-token raw dump.
- You need "what file should I patch / what did I already try" to be a direct query, not inferred.

Use **Graphiti** when:

- You need a knowledge graph of facts about the world, users, or an organization that evolves across weeks.
- Multi-tenant, multi-agent shared memory is part of the design.
- You're willing to run Neo4j/Kuzu and pay the LLM-extraction cost per ingest for the ontological payoff.
- Your retrieval patterns are richer than "which file, which test, which failed hypothesis."

They solve adjacent problems. The only reason a comparison is even interesting is that both ship as "memory for AI agents" — the honest answer is they're different products that happen to live on the same shelf.

## Installation

```bash
pip install "state-trace"      # library
pip install "state-trace[mcp]" # stdio MCP server for Claude Code / Cursor / Codex CLI

uv sync                       # repo development
pip install -e ".[mcp]"       # editable MCP install for local development
pip install -e ".[bench]"     # graphiti-core[kuzu] + datasets (for the headline benchmark)
pip install -e ".[llm]"       # OpenAI-backed live benchmarks + LLM ingestion
pip install -e ".[adapters]"  # LangGraph / LlamaIndex adapter shims
pip install -e ".[api]"       # FastAPI app
```

Distribution name: `state-trace`. Python import path: `state_trace`.

## Quickstart

```python
from state_trace import MemoryEngine

engine = MemoryEngine(capacity_limit=24.0, storage_path="memory.json")

task = engine.store(
    "Fix login by tracing the refresh token path",
    {"type": "task", "session": "auth-debug", "goal": "restore login", "file": "auth.ts", "importance": 0.92},
)
engine.store(
    "Login still returns 401 after refresh token exchange",
    {"type": "observation", "session": "auth-debug", "goal": "restore login", "file": "auth.ts",
     "blocks": [task.id], "importance": 0.88},
)
engine.store(
    "Authorization header is dropped before the retry request reaches auth.ts",
    {"type": "decision", "session": "auth-debug", "goal": "restore login",
     "related_to": [task.id], "file": "auth.ts", "importance": 0.91},
)

result = engine.retrieve("Why is login still broken?", {"session": "auth-debug", "goal": "restore login"})
```

## Current state, live hypotheses, failed attempts

The architectural wedge. These APIs return a live view of the session without re-ranking:

```python
state = engine.current_state(session="auth-debug", goal="restore login")
# → {"active_task": ..., "latest_observation": ..., "active_files": [...], ...}

failures = engine.failed_hypotheses(session="auth-debug")
# → [{"id": ..., "reason": ["superseded"], "content": "Login still returns 401 ..."}, ...]
```

`current_state` filters out invalidated and superseded nodes; `failed_hypotheses` surfaces them as "do not propose again" context. A general-purpose temporal graph has to infer this from fact updates; here it's a direct query.

## MCP Server

Install the official PyPI package:

```bash
python3 -m pip install --upgrade "state-trace[mcp]"
state-trace-mcp
```

Environment config:

- `STATE_TRACE_STORAGE_PATH` — durable path; `.db`/`.sqlite` uses the SQLite backend. Default: `~/.state-trace/memory.db`.
- `STATE_TRACE_NAMESPACE` — default namespace (e.g. the repo slug).
- `STATE_TRACE_CAPACITY_LIMIT` — working-memory budget (default `256`).

Tools exposed: `store`, `retrieve`, `retrieve_brief`, `record_action`, `record_observation`, `record_test_result`, `ingest_agent_log_file`, `current_state`, `failed_hypotheses`, `list_namespaces`, `graph_snapshot`.

### Install

<details>
<summary>OpenAI Codex</summary>

**One-line install:**

```bash
python3 -m pip install --upgrade "state-trace[mcp]"
codex mcp add state-trace -- state-trace-mcp
```

**Project-level install (one repo at a time):**

```bash
cd /path/to/your/repo
state-trace-mcp-config --namespace "$(basename "$PWD")" > .mcp.json
```

Or manually add to `.mcp.json` in the repo:

```json
{
  "mcpServers": {
    "state-trace": {
      "command": "/absolute/path/to/state-trace-mcp",
      "env": {
        "STATE_TRACE_STORAGE_PATH": "/Users/me/.state-trace/repo-x.db",
        "STATE_TRACE_NAMESPACE": "repo-x",
        "STATE_TRACE_CAPACITY_LIMIT": "256"
      }
    }
  }
}
```

Restart Codex after adding or changing `.mcp.json`.

**PATH-safe install:**

Use this if `codex mcp add state-trace -- state-trace-mcp` starts with `No such file or directory`.

```bash
python3 -m pip install --upgrade "state-trace[mcp]"
codex mcp add state-trace \
  --env STATE_TRACE_NAMESPACE=repo-x \
  --env STATE_TRACE_STORAGE_PATH="$HOME/.state-trace/repo-x.db" \
  -- "$(python3 -c 'from state_trace.mcp_config import resolve_entrypoint; print(resolve_entrypoint())')"
```

**Uninstall:**

```bash
codex mcp remove state-trace
```

For project-level installs, remove the `state-trace` entry from `.mcp.json`.

</details>

<details>
<summary>Claude Code</summary>

**One-line install:**

```bash
python3 -m pip install --upgrade "state-trace[mcp]"
claude mcp add state-trace -- state-trace-mcp
```

Or manually add to `.mcp.json` (project-level) or `~/.claude/settings.json` (global):

```json
{
  "mcpServers": {
    "state-trace": {
      "command": "/absolute/path/to/state-trace-mcp",
      "env": {
        "STATE_TRACE_STORAGE_PATH": "/Users/me/.state-trace/repo-x.db",
        "STATE_TRACE_NAMESPACE": "repo-x",
        "STATE_TRACE_CAPACITY_LIMIT": "256"
      }
    }
  }
}
```

**Uninstall:**

```bash
claude mcp remove state-trace
```

To uninstall manually, remove the `state-trace` entry from the config file.

</details>

<details>
<summary>Cursor</summary>

Open Settings → MCP → Add new MCP server, or add the same `mcpServers.state-trace` entry to `.cursor/mcp.json`.

```json
{
  "mcpServers": {
    "state-trace": {
      "command": "/absolute/path/to/state-trace-mcp",
      "env": {
        "STATE_TRACE_STORAGE_PATH": "/Users/me/.state-trace/repo-x.db",
        "STATE_TRACE_NAMESPACE": "repo-x",
        "STATE_TRACE_CAPACITY_LIMIT": "256"
      }
    }
  }
}
```

To uninstall, remove the entry from MCP settings.

</details>

<details>
<summary>Other MCP clients</summary>

Any MCP client that supports stdio transport can run:

```json
{
  "command": "/absolute/path/to/state-trace-mcp",
  "env": {
    "STATE_TRACE_STORAGE_PATH": "/Users/me/.state-trace/repo-x.db",
    "STATE_TRACE_NAMESPACE": "repo-x",
    "STATE_TRACE_CAPACITY_LIMIT": "256"
  }
}
```

Use `python3 -m state_trace.mcp_config` to print a complete config with storage, namespace, and capacity env vars.

To uninstall, remove the server entry from your client's MCP configuration.

</details>

## Online agent loop

```python
engine = MemoryEngine(capacity_limit=256.0)
ctx = {"session": "auth-debug", "goal": "restore login", "repo": "example/auth-service"}

engine.record_action('open "src/auth.ts"', {**ctx, "files": ["src/auth.ts"]})
engine.record_observation(
    "AttributeError: login still fails with a 401 in src/auth.ts",
    {**ctx, "files": ["src/auth.ts"], "status": "error"},
)
engine.record_action('edit "src/auth.ts"', {**ctx, "files": ["src/auth.ts"], "action_kind": "edit"})
engine.record_test_result(
    "pytest tests/test_auth.py::test_refresh_retry",
    "tests/test_auth.py::test_refresh_retry PASSED",
    {**ctx, "files": ["src/auth.ts", "tests/test_auth.py::test_refresh_retry"]},
)

brief = engine.retrieve_brief(
    "Which file should I patch and what test should I rerun?",
    {"session": "auth-debug", "goal": "restore login"},
    mode="small_model",
)
```

The brief fields: `patch_file`, `rerun_command`, `target_files`, `tests_to_rerun`, `current_state`, `failed_attempts`, `recommended_actions`, `evidence`, `symbols`, `patch_hints`, `confidence`, `token_estimate`.

## Trajectory ingestion

```python
engine = MemoryEngine(capacity_limit=256.0)
engine.store_agent_log_file("examples/data/agent_logs/marshmallow__marshmallow-1867.json")
```

Supported inputs: normalized `agent_log` JSON, raw SWE-agent `.traj` files, raw OpenHands event JSON logs.

### From iso-trace (Claude Code / Cursor / Codex / opencode sessions)

If you've accumulated session history with [`@razroo/iso-trace`](https://www.npmjs.com/package/@razroo/iso-trace), feed it directly:

```bash
# Export a session via iso-trace's CLI
npx @razroo/iso-trace export <session-id> --json --out session.json
```

```python
from state_trace import MemoryEngine
from state_trace.iso_trace_adapter import ingest_iso_trace_session

engine = MemoryEngine(capacity_limit=256.0, namespace="my-repo")
ingest_iso_trace_session(engine, "session.json")
```

The adapter reads iso-trace's documented Session → Turn → Event[] JSON and converts it to state-trace's `agent_log` format — typed nodes for files, edits, tests, errors. Months of accumulated harness history become queryable working memory without re-running the agent.

## Live solve-rate (next credibility step)

`examples/swebench_verified_solve_rate.py` scaffolds end-to-end solve-rate measurement: state-trace brief → LLM patch proposal → SWE-bench-Verified prediction JSONL. It does not run the swebench docker harness; that step is documented in the script's header.

```bash
python3 examples/swebench_verified_solve_rate.py --limit 5 --model gpt-5.1-mini --dry-run
```

## Storage backends

`MemoryEngine(storage_path=...)` picks the backend from the file extension:

- `.db` / `.sqlite` / `.sqlite3` — durable SQLite with WAL journal + FTS5 seed index. Recommended for long-running agent harnesses.
- any other path — JSON blob (simple, single-writer, fine for benchmarks).

See [ARCHITECTURE.md](./ARCHITECTURE.md) for the "why networkx + SQLite, not Neo4j" explainer.

## Namespaces

```python
engine = MemoryEngine(storage_path="memory.db", namespace="payments-api")
engine.retrieve("why is login broken?")  # scoped to payments-api by default
engine.retrieve("...", include_all_namespaces=True)  # opt out
```

Nodes without a namespace remain visible in every view so pre-namespace data is not lost.

## Framework adapters

```python
from state_trace.adapters import StateTraceLangGraphMemory, StateTraceLlamaIndexMemory

lg_memory = StateTraceLangGraphMemory(default_session="coding-session")
li_memory = StateTraceLlamaIndexMemory(session_id="agent-session")
```

Neither adapter imports the host framework; they satisfy the duck-typed memory contract used by each.

## FastAPI

```python
from state_trace.api import app  # POST /store, /retrieve, /retrieve_brief, GET /graph
```

Pass `"explain": true` on retrieve to include per-node score breakdowns.

## Tests

```bash
python3 -m pytest -q
```

## Benchmarks

Full set of repo-local benchmarks and their honest caveats lives in [BENCHMARKS.md](./BENCHMARKS.md). The SWE-bench-Verified row above is the only one that's at a scale worth citing externally.

## Positioning

See [**vs. Graphiti**](#vs-graphiti) above for the head-to-head comparison and [ARCHITECTURE.md](./ARCHITECTURE.md) for the architecture tradeoffs in detail. tl;dr: different products, adjacent problems — `state-trace` owns the narrow coding-agent working-memory lane; Graphiti owns weeks-of-history temporal knowledge graphs.