Harness Mem

harness-mem Skill

Mission

Provide persistent, cross-platform memory that keeps coding agent sessions continuous and retrieval-efficient.

Trigger Conditions

Use this skill when work needs:

• Cross-session continuity (resume context from previous sessions)
• Natural-language memory search across all past sessions
• Progressive retrieval (search → timeline → observations) instead of full-history stuffing
• Unified memory across multiple coding tools (Claude Code, Codex, OpenCode, Cursor)

Supported Client Setup

Codex

The harness-mem MCP server is configured automatically by harness-mem setup --platform codex. New Codex setup defaults to the local Streamable HTTP gateway at http://127.0.0.1:37889/mcp; existing stdio wiring remains valid unless the user explicitly migrates or rolls back.

harness-mem setup --platform codex
harness-mem doctor --platform codex

Rollback to stdio:

harness-mem mcp-config --transport stdio --client codex --write

If Codex reports url is not supported for stdio, inspect the [mcp_servers.harness] stanza before debugging the daemon. A single stanza must be either HTTP (url + bearer_token_env_var) or stdio (command/args/env); never leave both shapes in one block.

Cursor

Cursor is a Tier 2 supported local client. Use the repo/source setup flow, not an installed user skill copy:

harness-mem setup --platform cursor
harness-mem doctor --platform cursor

Cursor uses user-scoped ~/.cursor/mcp.json with mcpServers.harness-mem for MCP search. Cursor conversation capture uses official Cursor Hooks via ~/.cursor/hooks.json and the local hook spool; it is not the Codex local Streamable HTTP MCP default. After setup, Cursor may need an MCP reload, window reload, restart, or a new chat/session before the harness-mem MCP server appears.

Recommended Retrieval Sequence

1. harness_mem_resume_pack(project, session_id) — Get cross-platform resume context at session start
2. harness_mem_search({ query, project }) — Find relevant memories by natural language query, scoped to the current project
3. harness_mem_timeline — Expand temporal context around scoped search results
4. harness_mem_get_observations — Get full observation text for specific entries

Before any search-like call, resolve project from the current cwd/repo or from the project name the user mentioned. Do not use unscoped search when a project can be inferred. In parallel Claude / Codex projects, search the current project first and only broaden after the scoped result is insufficient.

S127 Bounded Search Rules

S127 makes search safer by keeping heavy retrieval off the daemon main loop. Treat these responses as normal control signals:

• harness_mem_search_facets is a scoped refinement tool. Do not call it with no arguments. Pass at least query, project, or tenant/access scope. An unscoped call returns 400 with search_facets_unbounded; narrow the request instead of retrying globally.
• Heavy harness_mem_search can return 503 (search_offload_queue_full, search_offload_unavailable, or similar). This means the daemon is applying backpressure so it does not freeze; it is not proof that memory is absent.
• On 503, retry once with a narrower query, the current project, and a smaller limit. If lexical evidence is enough, use vector_search=false. If it still returns 503, say memory search is temporarily busy and continue from SSOT/current files.
• Cross-project or unscoped search is only for explicit user requests, forensic/admin investigation, or after a scoped miss is reported.
• When reporting results, include the search scope in the answer (for example, project=/path/to/repo, project=unknown, hits=3, or 503 backpressure) so the user can tell whether the answer came from the right project.

Recommended Lifecycle Sequence

1. Session start: call harness_mem_resume_pack(project, session_id) to load context
2. During work: call harness_mem_record_checkpoint(...) at important milestones
3. Session end: call harness_mem_finalize_session(session_id) for summary generation

Available MCP Tools

Core Memory

• harness_mem_search — 3-layer progressive search (Step 1: candidate IDs)
• harness_mem_timeline — Temporal context expansion (Step 2)
• harness_mem_get_observations — Full text retrieval (Step 3)
• harness_mem_resume_pack — Cross-platform session resume context
• harness_mem_record_event — Record arbitrary memory events
• harness_mem_record_checkpoint — Record milestone checkpoints

Session Management

• harness_mem_sessions_list — List active sessions
• harness_mem_session_thread — Get events within a session
• harness_mem_finalize_session — End session with summary
• harness_mem_search_facets — Get scoped search facets; never call without query, project, or tenant/access scope

Administration

• harness_mem_health — Daemon health check
• harness_mem_admin_metrics — Usage metrics
• harness_mem_admin_consolidation_run — Trigger memory consolidation
• harness_mem_admin_consolidation_status — Check consolidation queue

Privacy Policy

• Semantic labels: tags (categorization)
• Policy labels: privacy_tags (access control)
• Block write: no_mem, block, skip, secret_block
• Private visibility: private, sensitive, secret
• Default retrieval excludes private records unless explicitly requested.