This page collects exact command, library and MCP rules. Start with the quickstart to try OKF; use this reference to check details and limits.
The document contract is the pinned OKF 0.2 specification. The Go module release, plugin release and okf_version are independent versions. Check installed binaries with okf version --json; find releases in GitHub Releases.
| Input | Interpretation |
|---|---|
Supported declaration in root index.md |
Selects that document contract: 0.2 or intentionally supported legacy 0.1. |
| No declaration | Defaults to 0.2, with the legacy fallback rules in §13. |
Present malformed okf_version |
A hard reserved-index error. Traversal defaults do not make it conformant. |
| Unknown future declaration | Retained; familiar data is consumed best-effort without claiming future conformance. |
Explicit --spec 0.1 or --spec 0.2 |
An assertion. A conflict with the declaration fails instead of overriding it. |
Write okf_version only in root index.md. Two pinned upstream revisions both call themselves 0.2: the original date-3fcbb9f profile remains the default; instant-0b87c52 requires offset-bearing datetimes in stale_after, sources[].last_modified and usage_window. Choose the latter with --temporal-profile instant-0b87c52 where supported. Dates cannot become instants without an explicit time and timezone. ADR 0003 records the revision choice.
go install github.com/skosovsky/okf/cmd/okf@latest
go install github.com/skosovsky/okf/cmd/okf-mcp@latest
okf version
okf version --json
okf init ./my-knowledge
okf validate --path ./my-knowledge --spec 0.2
init requires an absent directory with an existing parent. It never overwrites an existing file, directory or symlink. See the init contract.
These two files are also a minimal conformant bundle:
index.md:
---
okf_version: "0.2"
---
# Concepts
* [Minimal](minimal.md) - A minimal note.
minimal.md:
---
type: Unknown Producer Type
---
A minimal note.
type is the only always-required concept field. Provenance, verification, lifecycle and computation are optional families. Replace the example body with knowledge from provided materials; the quickstart walks through that operation.
| Rule | Consequence |
|---|---|
Add generated only for a known producer |
Transaction actor, Git author, file owner and current user are not implicit document producers. |
Add sources from actual materials |
Attribute claims with footnotes keyed by sources[].id. |
Record verified after an actual check |
Authorship, Git, timestamps, migration and format validation do not create verification, credibility, lifecycle status or freshness. |
| Preserve unknown keys, types and content | Future fields remain available without narrowing them to the toolkit’s typed model. |
Keep sanctioned computation in a standalone type: Attested Computation concept |
See computation for execution boundaries. |
For effective v0.2 reading, use generated and sources. Use timestamp only when generated is wholly absent, and legacy # Citations only when sources is absent. Presence, including a malformed replacement, suppresses fallback. This predicate is independent of whether the version was defaulted, declared or explicitly selected, including v0.1 and future versions.
GeneratedPresent/SourcesPresent describe presence; TimestampAllowed/CitationsAllowed describe replacement absence; TimestampActive/CitationsActive additionally require an actual legacy form. Active citations require an exact parser-owned # Citations heading. A numeric [1] in prose alone is not legacy evidence: an undeclared bundle containing only that prose resolves as native v0.2 target-noop.
A bare verified value and a one-item list have the same typed semantics without rewriting their YAML. Trust is derived only from verified; trust, raw/effective lifecycle status and staleness are separate projections. When sources and old citations coexist, reading prefers sources and preserves the legacy bytes. Migration blocks with reconcile_sources_and_citations instead of merging or deleting them.
Canonical examples are registered in the fixture corpus: minimal, Appendix A, verification, lifecycle, computation, legacy, mixed, future and adversarial cases. Synthetic examples use reserved domains such as example.invalid.
| Layer | What it checks |
|---|---|
| Base | UTF-8, parseable concept frontmatter, non-empty string type, reserved-file structure. |
| Strict | Advisory checks of present v0.2 fields, attribution, lifecycle and computation shapes. |
| Links | Advisory internal-link diagnostics. |
| Orphans | Advisory coverage by indexes, only when requested. |
Unknown types, keys or runtimes, absent optional fields, broken links and missing indexes do not become base errors. A reserved index may start with a title and introduction before its linked groups. Unknown root frontmatter keys alongside a valid okf_version survive. Wrapped lines in a flat log.md item remain one entry. Strict attribution ignores literal footnotes in code spans.
Parser-owned Markdown processing has separate 16 MiB limits for a complete document (bundle.MaxMarkdownDocumentBytes) and an already separated body (bundle.MaxMarkdownBodyBytes). Error classification order is cancellation, invalid UTF-8, bundle.ErrMarkdownResourceLimit, then parser/ownership errors. bundle.MarkdownResourceLimitError exposes resource kind, limit and saturated observed size. Context APIs return exact zero results on rejection. These limits are not the same as the aggregate search limits.
| Command | Purpose |
|---|---|
init |
Create a draft bundle in a new directory. |
setup |
Preview/apply a managed copy of ordinary Markdown into a new directory. |
search |
Search sections using all query terms. |
validate |
Check the document contract and optional diagnostics. |
info |
Inspect version-aware projections. |
parse |
Parse one document; optionally emit JSON projections. |
fmt |
Format one document; -w writes it. |
index |
Generate navigation indexes. |
graph |
Project links and optional typed relations. |
view |
Export a standalone HTML viewer; --lang en|ru selects initial interface language, default en. |
migrate-prepare |
Prepare editable migration input templates outside the source bundle. |
migrate |
Preview/apply v0.1 → v0.2 migration. |
temporal-upgrade |
Preview/apply explicit date → instant mappings within v0.2. |
version |
Report program and supported document versions. |
help |
Show CLI help. |
okf search ./knowledge --query "retry deadline" --limit 5 --json
okf setup --source ./notes --target ./prepared-knowledge --type Note --json
okf validate --path ./knowledge --spec auto --strict --as-of 2026-07-29
okf validate --path ./knowledge --check-links --check-orphans
okf validate --path ./knowledge --spec 0.2 --strict --temporal-profile instant-0b87c52 --as-of 2026-09-23T11:00:00Z
okf info ./knowledge --spec auto --as-of 2026-07-29
okf parse ./knowledge/minimal.md --temporal-profile instant-0b87c52 --as-of 2026-09-23T11:00:00Z --format json
okf fmt ./knowledge/minimal.md
okf fmt ./knowledge/minimal.md -w
okf index ./knowledge --spec auto
okf graph ./knowledge --profile skosovsky/okf-v0.2-instant --format ntriples --as-of 2026-09-23T11:00:00Z
okf view ./knowledge --output ./knowledge.html --lang en
Use an explicit --as-of for reproducible staleness. Parsing, formatting, indexing and graph projection do not migrate provenance, stamp producers or timestamps, add verification, or bump okf_version. Unknown data remains lossless within supported parser-backed changes. See the toolkit guide for complete workflows.
| Package | Responsibility |
|---|---|
bundle |
Load documents/assets and expose lossless YAML plus typed v0.2 views. |
validator |
Base, strict, links and index-coverage diagnostics. |
graph |
Standard links, typed relations and export formats. |
retrieval |
Shared section search for Go, CLI and MCP. |
setup |
Preview and digest-bound Apply for ordinary Markdown. |
viewer |
Project and render a standalone HTML viewer; Render defaults to English, RenderWithOptions chooses language. |
mutation |
Preview and apply semantic desired-state changes. |
store |
Transaction, revision, compare-and-swap and receipt contracts. |
store/fs |
Filesystem implementation with journal durability. |
backfill |
Extract bounded Git evidence, validate analyzer proposals and prepare reviewed history reconstruction. |
upkeep |
Capture repository baselines, detect affected knowledge and check decisions against current fingerprints. |
b, err := bundle.LoadBundle("./knowledge")
if err != nil {
return err
}
report := validator.ValidateBundle(b, &validator.ValidatorConfig{
Strict: true,
CheckLinks: true,
CheckOrphans: true,
})
if !report.IsConformant() {
return errors.New("bundle is not conformant")
}
The fragment uses errors, github.com/skosovsky/okf/bundle and github.com/skosovsky/okf/validator imports inside a function returning error.
Typed accessors are projections over lossless YAML and return defensive copies. Get, YAML-node access and caller-owned structs remain authoritative for unknown data: Bring Your Own Types. Raw frontmatter/body remain available rather than being forced through a closed schema. Non-Markdown source/computation assets are inert revision-visible files; reading them does not execute or fetch them.
Mutation previews staged output, validates the final bundle, preserves untouched presentation and commits through compare-and-swap (CAS) and journal durability. Semantic migration is separate from parsing/formatting/indexing/graph. Transaction actors and store.ChangeSet/receipt formats are independent of document actors. Legacy wire/profile versions change only under their own contracts.
search and MCP search_sections require all distinct normalized terms in a section’s Markdown, heading or concept title. Unicode case folding and NFC normalize terms; there is no stemming, translation, synonym expansion or semantic search. Markdown code is inert searchable text, not executable input; fenced pseudo-headings do not split sections. Index/log files are excluded.
Hits include original snippets, inclusive physical line ranges, percent-encoded locators, the whole-file SHA-256 and a snapshot fingerprint. Recheck the digest or repeat search after edits. The fingerprint is not a store revision, authorization proof or evidence of content truth. Ranking is lexical BM25 (k1=1.2, b=0.75; Markdown/heading/title weights 1/3/2), then concept ID and starting line for ties.
| Search bound | Value |
|---|---|
| Query / distinct terms / normalized term | 1–512 Unicode characters / 32 / 4096 characters |
| Requested hits | 1–100; default 20 |
| Captured files / aggregate bytes / one file | 10,000 / 64 MiB / 16 MiB |
| Sections / indexed tokens | 100,000 / 1,000,000 |
| Tree depth / path bytes | 64 / 4096 |
| Heading and title / snippet | 1024 UTF-8 bytes each / 512 Unicode characters |
| JSON response | 1 MiB |
total counts matching sections; truncated reports omitted hits. There is no cursor or persistent index. Refine terms or raise the limit up to 100. A limit, parse error or cancellation fails without partial results. Loading excludes internal symlinks and rejects symlink roots/escapes. Full section-search contract.
setup preserves the source and previews copies into a new target. Review its plan and pass its exact digest to apply; source changes, target collisions and unsupported links/assets block publication. The note type is explicit; setup does not infer sources, producers, verification or freshness. Full Markdown preparation contract.
The server has no -root flag. Each call supplies an accessible absolute bundle_path; host and process permissions determine accessible files. Connection walkthrough.
{"mcpServers":{"okf":{"command":"okf-mcp","args":[]}}}
| Tool | Operation |
|---|---|
list_concepts |
List documents. |
read_concept |
Read raw and interpreted document data. |
validate_bundle |
Validate a bundle. |
get_semantic_graph |
Read graph projections. |
write_concept |
Compatibility write interface. |
search_concepts |
Bounded literal-substring search. |
search_sections |
Ranked sections containing all lexical terms. |
get_neighbors |
Navigation and typed-relation neighbors; provenance sources remain separate. |
preview_concept_patch |
Preview a desired-state patch. |
apply_concept_patch |
Apply a revision/digest-bound patch. |
preview_v02_migration |
Preview legacy migration. |
apply_v02_migration |
Apply the matching migration. |
preview_temporal_upgrade |
Preview explicit date-to-instant mappings. |
apply_temporal_upgrade |
Apply the matching temporal plan. |
There are fourteen tools. Compatibility tools retain their text fallbacks. Structured outputs are schema-validated. search_concepts and get_neighbors return total/truncated when bounded output omits hits/edges. There is no cursor: narrow input, or request a whole graph if it fits. A hard resource_limit fails the call rather than returning a partial page. Invalid inputs produce stable codes and bounded field guidance. Query contract.
search_concepts ranks ID and metadata matches ahead of body matches; it is literal search, separate from section ranking.
Patch apply needs expected_revision and the preview plan digest. Migration has a different proof contract. Actor metadata is not authentication. Bundle paths obey containment/no-follow rules; a resource value is not permission to access files, network, shell or secrets. Mutation trust boundaries.
MCP actor-bearing fields have a 256-byte transport/resource limit before domain validation. At 257+ bytes the error is resource_limit, not invalid actor. Within that bound shared ValidActor decides semantics. This is an adapter limit, not a length rule for bundle/store actors.
In structured MCP JSON, every present usage_count is a canonical decimal string matching ^(0|[1-9][0-9]*)$, or null for nullable output fields. Patch input rejects uint64 overflow. Strings avoid float64 precision loss when decoding Arguments, including MaxUint64; legacy text output is unchanged.
| Operation | Allowed selector forms |
|---|---|
set_usage_window |
Shared: neither source_id nor source; identified: non-empty source_id; exact anonymous: source present, its id absent. |
remove_source |
Identified or exact anonymous, with the same definitions. No shared form. |
Empty source_id, mixed forms, unknown selector forms and ambiguous exact anonymous matches are rejected. Source metadata is not matched through a guessed identity.
The migration guide shows a runnable example. This section defines the detailed behavior.
Migration validates each supplied actor, timestamp, citation, generated-at, computation and asset field before source resolution or transition planning, even for a rootless bundle or target-noop. Invalid individual input is rejected rather than ignored. An unrenderable individual migration field is invalid_request.
A legacy timestamp has no producer. Converting it into generated.at requires caller-provided generated.by. CLI --actor is that document producer, not store.ChangeSet.Actor; the adapter uses a separate internal transaction principal. Preview may omit it and receive provide_generated_by; writing a generated change needs the producer. Conflicting timestamp/generated.at requires explicit policy. CLI preserves the legacy timestamp and rejects conflicts. A type-only legacy bundle without timestamps changes only the root version; no actor/time is required and no generated is invented.
Explicit citation, generated-at and computation paths must name existing bundle documents. A missing path blocks with migration_document_missing, with an empty manual-action list; mappings cannot create the missing document.
Migration never infers source titles, authors, usage or last-modified dates, claim mappings, verification or trust, lifecycle status/stale dates, credibility, receipts/verdicts, successful attestation, or an Attested Computation from narrative prose.
CLI --citation-mappings <json-file> and MCP accept the same closed array; there is no wrapper object:
[{"path":"retries.md","entries":[{"legacy_number":1,"source_id":"requirements","title":"Training requirements","resource":"https://example.invalid/requirements"}]}]
| Field | Rule |
|---|---|
path |
Bundle-relative Markdown path, including root index.md, logs and nested files; not a concept ID. |
legacy_number |
Nonzero number selecting the parser-owned [n] citation entry. |
legacy_entry |
Exact raw entry, including an unnumbered bullet or URL. At least one selector is required. |
| Both selectors | Both must match the same entry. |
source_id |
Explicit stable identity. Reuse requires consistent metadata. |
title, resource |
Optional explicit metadata. No inferred title or destination. |
legacy_entry is valid UTF-8, 1–4096 bytes, nonblank according to strings.TrimSpace and contains no NUL. TAB/LF/CR are allowed; other C0 controls and DEL are rejected. Matching does not trim, fold case, canonicalize URLs or normalize newlines. Exact bytes are part of authorization and the digest: LF and CRLF are distinct.
Duplicate nonzero numbers always fail within one document. Reuse of raw legacy_entry is valid only in distinct complete number+entry pairs. An entry-only selector overlaps any reuse of that raw text; two entry-only copies are also invalid. An entry-only match to duplicate raw entries is ambiguous. Canonical ordering is path, number, exact raw entry. Unknown fields, unsafe paths, oversized values/files/arrays, inconsistent metadata and incomplete mappings fail closed.
The CLI loader bounds its JSON file at 16 MiB, documents at 10,000, entries at 10,000, each string at 4096 bytes, legacy_number at 1,000,000 and JSON depth at 16. These are input-file limits, not general Markdown limits. Loader implementation.
Only claim markers whose ownership the Markdown parser can prove are rewritten. Ambiguous, duplicate or unresolved Markdown blocks migration. Inline/fenced code and raw HTML are opaque: marker-like text there neither satisfies nor fails a claim replay assertion. Literal [^label] in inline or multiline code spans is opaque; a real shortcut footnote in prose participates.
On v0.1-to-v0.2, a number selects an entry in the active legacy section. On target-noop, an explicit mapping asserts the already-migrated state: the keyed footnote must match and, for a concept, so must the structured source ID and supplied metadata. It never converts bare [1] prose. An active legacy section on the v0.2 target blocks replay.
For each nonzero legacy_number, the selected parser-owned [n] marker must be gone and the normalized keyed [^SourceID] reference must exist. Entry-only mappings have no claim-reference requirement. A remaining selected marker, missing reference or wrong reference blocks with migration_replay_mismatch at the exact parser-owned span, with no invented manual action, proof or plan authorization.
A normalized per-document source-ID/footnote-label collision blocks with normalized_footnote_label_collision and disambiguate_citation_entry, also on target-noop. An existing-document collision reports the same exact span. This is distinct from an unrenderable individual field (invalid_request). Both outcomes write nothing.
Source resolution runs exactly once before preview. Preview and apply use the same complete expected_source: requested_selector, declaration state (declaration_present, declaration_valid, declaration_raw, declared_version), resolved version/provenance and transition fields, plus ordered legacy candidates and blockers. Apply rejects changed resolution or its evidence. A present malformed root version is not an absent/default source; unsupported canonical future declarations remain declared and block v0.1 migration.
| Transition | Apply requirements |
|---|---|
v0.1-to-v0.2 |
Preview proof format_version: 2, non-empty resolution_digest, non-empty expected_plan_digest, and identical full expected_source. Earlier proof formats are rejected. |
Live target-noop over MCP |
Same frozen expected_source, no proof or plan digest; target-state input is still validated. |
| Blocked preview | Cannot be applied. |
There is no separate migration expected_revision: proof.base_revision is authoritative when proof exists. A successful transition preview with a non-empty plan digest returns a content-free proof. It freezes request and source resolution, revision digests, read paths, write path+digest pairs, deletes, renames, affected and reverse-impact references, and changed file/reference summaries. Arrays are non-null. The proof contains no file bytes, frontmatter or body. Noop/blocked MCP preview omits proof.
A proof-bound transition apply may return transition-noop only after authenticating and rebuilding the exact proof and plan digest. It returns before opening the store and creates no .okf.
The entire staged bundle must validate as v0.2 before atomic publication. The physical write/rename of root index.md is last: its version declaration is the transaction’s final visible publication. Unknown YAML, Markdown and assets are preserved.
Every preview, rejected, blocked, invalid, cancelled or other non-publication path leaves the complete filesystem tree path-for-path and byte-for-byte identical, with no .okf or staging artifacts. Only an authorized actual commit may publish changes. An identical successful replay returns the recorded result without a second publication.
target-noop has adapter-specific behavior:
| Surface | Store/receipt behavior | Bundle files |
|---|---|---|
MCP live target-noop |
No proof; store is not opened; no .okf. |
Identical paths and bytes. |
| CLI dry-run | Builds proof without opening store. | Identical paths and bytes. |
CLI --write |
Commits empty CAS; durably creates or replays receipt under .okf. |
Revision-visible files have identical paths and bytes. |
The CLI write case is an actual receipt publication; it is not covered by the non-publication no-artifact rule. Transaction durability evidence (store.CommitReceipt) and computation runtime receipt (executor.receipt) are separate contracts.
| Code | What the caller must resolve |
|---|---|
provide_citation_mapping |
Missing/unresolved mapping, or number and raw entry contradict the actual citation. |
disambiguate_citation_entry |
Duplicate number/raw selector match or normalized source/footnote-label collision. |
disambiguate_citation_destination |
Parser ownership cannot identify one link destination. |
normalize_citations_section |
Opaque/unowned extra content in the legacy section. |
reconcile_sources_and_citations |
Structured sources coexist with the legacy section. No merge, deduplication or deletion is inferred. |
repair_invalid_utf8 |
Invalid UTF-8. |
provide_generated_at |
Required generation time is absent. |
provide_generated_by |
Required producer is absent. |
Duplicate raw-entry selection is different from destination ambiguity. migration_document_missing and migration_replay_mismatch are blocking errors without an invented manual-action code. See migration preparation for editable templates and exact byte spans, and the normative migration policy.
This is separate from v0.1 migration. Supply a mapping for each observed date in stale_after, usage_window.from/to and sources[].last_modified. The tool never invents midnight or end of day. sources[N] uses the zero-based position in the previewed revision. Unresolved values block apply.
{"mappings":[{"concept":"payments/retries","path":"stale_after","from":"2026-09-26","to":"2026-09-26T18:00:00+07:00"}]}
Save the complete mapping file as temporal-mappings.json. Review the preview, then use the exact returned preview.BaseRevision and plan_digest:
okf temporal-upgrade ./knowledge --id temporal-2026-09 --actor human:reviewer --mappings temporal-mappings.json
okf temporal-upgrade ./knowledge --id temporal-2026-09 --actor human:reviewer --mappings temporal-mappings.json --write --base-revision 'sha256:<preview.BaseRevision hex>' --plan-digest 'sha256:<preview plan_digest hex>'
Apply rebuilds the plan against the current revision and publishes one transaction. If files changed, preview again and review positions/digest. Unsupported YAML presentation, such as an alias or tagged quoted scalar the lossless patcher cannot prove, fails closed. Rewrite that scalar in a plain or unquoted core-tag form and preview again. Select instant-0b87c52 to read the result; the old date profile remains default. Temporal contract.
relations is a skosovsky/okf extension/tooling policy, not upstream OKF v0.2. Standard Markdown links remain the format’s navigation and relationship mechanism. Graph profiles (skosovsky/okf-v0.2, skosovsky/okf-v0.2-instant, legacy-v0.1) are independent of document version. Exports include dot, mermaid, json-ld and ntriples; extension inclusion is explicit via --extension-relations include.
The relation-reference grammar is <escaped-concept-id>[#<fragment>]. Escape only # belonging to the ID with the logical two-byte \#; the first unescaped # starts the fragment:
| Logical reference | Meaning |
|---|---|
source#part |
Concept source, fragment part. |
source\#part |
Concept whose ID is source#part, without fragment. |
After the delimiter, backslashes are ordinary fragment bytes. Stray/noncanonical ID escapes (source\part, source\, source\\#part) fail. Existing references without escaped hashes retain their exact bytes. YAML can carry 'source\#part'; JSON carries "source\\#part" because it escapes the backslash. This additive canonical encoding does not alter graph/MCP schema shape. Store receipt v1 keeps references as []string with lexical canonical wire ordering; escaped-hash support is a canonicalization fix, not a format migration.
OKF records computation and attestation contracts. computation, executor.resource and attester.resource are inert data. Their presence does not execute content. Execution requires a separately trusted runtime and authorization.
The pinned spec permits an agent to supply values only for declared parameters and forbids it to author or edit sanctioned computation. OKF v0.2 does not define runtime discovery, parameter binding implementation, receipt/verdict wire format, attester ABI, portability, sandboxing or cache. The toolkit does not invent these mechanisms. store.CommitReceipt is neither stored in nor accepted as executor.receipt.
Body instructions cannot override frontmatter, lifecycle/freshness signals, authorization or trusted-runtime policy. LLM prose is not an attestation verdict.
| Skill | Purpose and required tools |
|---|---|
open-knowledge-format |
Author/read/validate/export/migrate; installed okf or connected okf-mcp. Pinned to the v0.2 specification. |
okf-maintain |
Review repository knowledge after code/contracts change; also needs okf-upkeep. |
okf-backfill |
Evidence-bound Git-history reconstruction; needs okf-backfill, backfill/PROTOCOL.md and its schemas. |
Copy the selected directory from skills/ into the host’s skills directory, keeping its relative references. Skill files do not install binaries or grant permissions. Verify actual host registration and tool connectivity; the skill guide shows a first invocation.
If MCP is missing, check installed CLI or source-checkout Go commands. If neither exists, report manual inspection separately from a completed tool check. Viewer output must be local and outside the bundle; replacing existing output needs authorized --overwrite.
okf-maintain captures a baseline before repository edits, compares affected notes with code/contracts, and records an updated or reasoned unaffected decision bound to the final fingerprint. okf-backfill follows Git extraction, evidence-bound analysis, reviewed plan, authorized apply and independent verification through the Go pipeline.
skills.sh.json, both plugin manifests and skills-lock.json register the three skills. skill-dependencies.json lists workflow dependencies by name/path without duplicating schemas. CI checks dependencies against MCP catalog and CLI dispatch, checks links/assets, and copies only skills/ to an isolated installation root. The package checker uses the Go YAML parser and resolves inline/reference-style Markdown links inside the installed tree.
go test ./...
go vet ./...
git diff --check
node scripts/update-skills-lock.mjs --check
node scripts/check-skill-package.mjs
Recompute the skill lock after changed skill content/references are stable. A filesystem/package smoke test proves packaging, not activation or tool invocation in Codex, Claude Code or skills.sh. CI does not exercise those hosts: check each claimed host with a real client before making a release claim.
The repository’s own public bundle begins at knowledge/index.md; repository knowledge explains maintenance. Its published viewer is a reproducible snapshot, separate from the bilingual training example.