--- title: "Link units" description: "Link an existing folder of .10x.json symbol units into a single .10x.tar library, with no source scan." icon: material/link-variant --- Link a folder of `.10x.json` symbol units from a prior compile into a single `.10x.tar` library, with no source scan. It is the same [Compiler app](../../../compiler/) invoked with link-only arguments: the units folder is also the output folder and no source is mounted, so the engine reuses the units already on disk and [merges them into the library](../../../../compile/link/). Use it to: - re-link after editing or pruning units - assemble a library from a units tree built piecemeal - rebuild a library from the output folder of a prior [`log10x_compile`](compile.md) Same wait shape as compile: the link waits inline up to `max_wait_ms` (default 45s). Linking is usually fast, so it normally returns the finished library in one call. A very large units tree returns a running `job_id` to poll with [`log10x_compile_status`](compile-status.md), and `max_wait_ms: 0` returns the `job_id` immediately. ## :material-code-braces: Example !!! tenx-ask "You" I pruned the units folder. Re-link it into a library. !!! tenx-answer "Log10x" Linked 412 units into `symbols.10x.tar` (3.4 MB) in 6s. No source scan, no new files traversed. Symbols by type: class 1,180, log 642, exec 410, enum 96. ## :material-chat-question-outline: More to ask - *"link `/work/units` and call the library `payments`"* - *"rebuild the library from my last compile's output folder"* - *"the units tree is huge, kick off the link and give me a job_id"* ## :material-check-decagram-outline: Prerequisites The Compiler flavor, docker-first: `auto` and `docker` pull `log10x/compiler-10x`, and `local` runs a Compiler-flavor `tenx`. The Runtime flavor is refused. This is the CLI tier, so it needs no Kubernetes, deployed app, or Log10x account. `units_path` must hold at least one `.10x.json` unit from a prior [`log10x_compile`](compile.md). An empty folder is refused with nothing to link. ## :material-code-json: Schema and samples ??? tenx-input-example "Input example" Re-link a pruned units folder into a named library. ```json { "units_path": "/work/symbols-out", "library_name": "payments" } ``` ??? tenx-input-schema "Input schema" Agent-facing JSON Schema (the canonical shape the MCP server publishes via `tools/list`): ```json { "type": "object", "properties": { "units_path": { "type": "string", "description": "Absolute path to a folder of .10x.json symbol units (produced by a prior compile) to link into a single .10x.tar library. Traversed recursively; the existing units are merged with NO source re-scan, and the .10x.tar is written into this same folder." }, "library_name": { "type": "string", "default": "symbols", "description": "Base name for the linked .10x.tar and the runtimeName. Sanitized to [A-Za-z0-9_.-]." }, "mode": { "type": "string", "enum": ["auto", "docker", "local"], "default": "auto", "description": "Execution backend, same contract as log10x_compile: `auto` prefers the Compiler image, `docker` forces it, `local` uses a Compiler-flavor tenx. The Runtime flavor is refused." }, "timeout_ms": { "type": "integer", "minimum": 10000, "maximum": 3600000, "default": 600000, "description": "Hard cap on link wall time in ms. Default 600,000 (10 min). Linking is much faster than scanning, but a very large units tree can still take minutes." }, "max_wait_ms": { "type": "integer", "minimum": 0, "maximum": 300000, "default": 45000, "description": "How long to wait inline (ms) for the link to finish before handing back a job_id to poll. Default 45,000 (45s). Linking usually finishes inside this and returns the library in ONE call. A very large units tree returns a running job_id you poll with log10x_compile_status. 0 = fire-and-forget." } }, "required": ["units_path"], "additionalProperties": false } ``` Source: [`src/tools/compile-link.ts`](https://github.com/log-10x/log10x-mcp/blob/main/src/tools/compile-link.ts). ??? tenx-output-example "Output example" Representative envelope for a fast link that finished inside `max_wait_ms`. The bounded-sync path returns the [`log10x_compile_status`](compile-status.md) readout the moment the link completes, so the shape matches that tool: `data.payload.job_status` is `completed`, with the produced units, the linked library, and the link diagnostics. The `diagnostics.scan_health` block is null on a link (no source scan), and `link_report` populates once the `compiler-10x` image carries the engine diagnostics change. ```json { "schema_version": "1.0", "schema_epoch": "2026-05-25", "tool": "log10x_compile_status", "generated_at": "2026-06-15T09:12:04.118Z", "view": "summary", "status": "success", "summary": { "headline": "Link job `7b2e9c41-...` done: 412 units → /work/symbols-out/payments.10x.tar (3.4 MB)." }, "data": { "status": "success", "decisions": { "threshold_used": null, "threshold_basis": "default" }, "source_disclosure": {}, "scope": { "window": "payments_compile", "window_basis": "explicit", "candidates_count": 412, "candidates_usable": 1 }, "payload": { "job_id": "7b2e9c41-3f5a-4d8e-9b21-6c0f1a2d7e44", "job_status": "completed", "mode": "docker", "image": "log10x/compiler-10x", "exit_code": 0, "elapsed_ms": 6240, "timed_out": false, "sources": "link /work/symbols-out", "output": { "folder": "/work/symbols-out", "unit_count": 412, "empty_unit_count": 0, "library_files": [ { "path": "/work/symbols-out/payments.10x.tar", "bytes": 3565158 } ] }, "diagnostics": { "results_available": true, "phases": [ { "operation": "link", "status": "ok", "traversed_files": 412, "scanned_files": 0, "output_files": 1, "warns": 0, "errors": 0 } ], "scan_health": null, "link_report": { "merged_files": 412, "skipped_files": 0, "excluded_by_folder": 0, "excluded_by_file_name": 0, "merged_repos_count": 1, "non_merged_repos_count": 0, "symbols_by_type": { "class": 1180, "log": 642, "exec": 410, "enum": 96 }, "symbols_excluded_by_type": 0 } }, "log_tail": [] }, "human_summary": "Link job 7b2e9c41-... completed via docker in 6s: 412 symbol units, linked to /work/symbols-out/payments.10x.tar (3.4 MB). No files failed to scan. Linked 412 unit files; symbols by type: class 1180, log 642, exec 410, enum 96." }, "actions": [ { "tool": "log10x_validate", "args": { "extra_args": [["symbolPaths", "/work/symbols-out"]] }, "reason": "smoke-test the compiled library against a few sample event lines (supply input_lines)" } ], "truncated": false, "warnings": [] } ``` A units tree too large to link inside `max_wait_ms`, or a call with `max_wait_ms: 0`, returns the handoff envelope instead, with `data.payload.job_status: "running"` and a `log10x_compile_status` action carrying the `job_id`. ??? tenx-output-schema "Output schema" The `data` block inside the [chassis envelope](../index.md). On the bounded-sync completion path the payload is the [`log10x_compile_status`](compile-status.md) shape: ```typescript interface CompileLinkPayload { job_id: string; job_status: 'running' | 'completed' | 'failed' | 'timed_out'; mode: 'docker' | 'local'; image: string | null; exit_code: number | null; elapsed_ms: number; timed_out: boolean; sources: string; output: { folder: string; unit_count: number; empty_unit_count: number; library_files: Array<{ path: string; bytes: number }>; }; diagnostics: { results_available: boolean; phases: Array<{ operation: string | null; status: string | null; traversed_files: number | null; scanned_files: number | null; output_files: number | null; warns: number | null; errors: number | null; }>; // null on a link (no source scan). scan_health: { files_failed: number; failed_by_language: Record; failure_samples: Array<{ name: string; language: string; reason: string }>; } | null; // Populated once the compiler-10x image carries the engine // diagnostics change; null otherwise (graceful degradation). link_report: { merged_files: number; skipped_files: number; excluded_by_folder: number; excluded_by_file_name: number; merged_repos_count: number; non_merged_repos_count: number; symbols_by_type: Record; symbols_excluded_by_type: number; } | null; }; log_tail: string[]; } ``` When the link overruns `max_wait_ms`, the handoff payload is smaller: `{ job_id, job_status: 'running', mode, image, library_file, runtime_name, sources, started_at, timeout_ms, log_file, units_path, unit_count }`. Poll [`log10x_compile_status`](compile-status.md) with `job_id` for the completed shape above. Envelope-level fields the agent should also read: `status` (top-level mirror of `data.status`), `summary.headline` (1-line answer), `data.human_summary` (the quotable plain-English summary), `actions[]` (next-call chain hints as `{tool, args, reason}`), `truncated`, and `schema_epoch`.