io.github.vlad-public-code/valem

Tools

• create_model

  Create a new model from a declarative ModelSpec. The spec carries the JSON schema plus derivations (computed fields), constraints (invariants), and optional effects. Returns the created id. Fails (isError) on an invalid spec. If the requested id is already taken, a numeric postfix (-2, -3, …) is appended so the create still succeeds — always read the returned id, it may differ from the one you sent. When paired with a browser (remote_with_browser mode), ALWAYS include a viewDefinition in the spec so the model is immediately visible/usable in the sandbox — do not omit it and wait to be asked for one afterward. See the valem://guide/view-system resource for the component catalog.

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• delete_model

  Remove a model from the registry. Fails (isError) if the model does not exist.

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• download_blob

  Fetch a blob's bytes by id, base64-encoded in the result. Pass 'modelId' to fetch a blob referenced by a specific model (access-scoped); omit it for a direct store fetch. Large blobs may exceed the result-size limit — this channel suits small binaries only.

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• dry_run

  Compile a candidate ModelSpec in an ISOLATED throwaway runtime, apply optional sample mutations, and return the resulting merged state (base + derived) — WITHOUT registering it in the live registry. Use this to preview the full reactive cascade of a draft spec.

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• eval_expression

  Evaluate a single JSONata expression against a sample input document and return the computed value, or the exact compile/eval error. Write the expr exactly as in a derivation/constraint 'expr': bare dot-paths, no leading $ (e.g. "loan.amount * loan.annualRate / 1200"). Use this to verify an expression before putting it in a spec — it uses the same compiler the runtime validates against. If the expression calls a library function, pass the model's library definition as 'library' — without it every $myFn(...) call fails as undefined.

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• evolve_spec

  Apply an incremental SpecEvolution diff to a model, preserving live state. Returns the new version. Fails (isError) if the evolved spec is invalid, if expectedVersion no longer matches, or if a schema change would strand existing state. Prefer targeted diffs (upsertSchemaNodes/upsertSchemaDefs, upsertComponents, upsertConstants) over resending a whole section (newSchema/newViewDefinition/newConstants).

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• explain

  Explain why a field is what it is: returns the recent derivation/constraint trace records for a path from the in-memory ring buffer (inputs, expression, result). For a constraint use the synthetic path "$constraint:<id>". Trace records can be bulky — pass 'limit' to return only the most recent N.

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• get_audit

  Query a model's durable, append-only audit trail (newest-first): one record per committed reactive cycle (mutations, derivedUpdated, traces, flaggedConstraints, dispatchedEffects, source, sequence). This is the queryable superset of get_history/explain — it survives the in-memory ring buffer rolling over. Filter with an optional 'pathPrefix' (canonical address), an ISO-8601 'from'/'to' window, and 'limit'. (Embedded mode keeps this in memory for the session; remote/paired mode reads the server's durable store.)

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• get_domain_guidance

  Get vetted instructions for the hard modelling shapes this domain involves (progressive tax/fee charges, per-period schedules, classification, date math, group-by, …). Read the model description in ANY language, pick the matching topic ids, and call this BEFORE authoring the spec — then follow what it returns. Available topics: - amortization_schedule — A computed array / per-period schedule: an amortization table, time series, or per-period breakdown (one row per period). - group_by — Group-by / aggregation over an array: subtotals, counts, sums per category. - date_math — Date arithmetic: days/months/years between dates, elapsed duration, age from a birth date. - classification — Deriving a label / tier / band / risk level / status from data via thresholds. - currency_conversion — Currency / FX conversion of an amount by an exchange rate. - status_field — A status / state field with flags or labels derived from the current status. - rank_percentile — Rank / percentile / leaderboard / quartile over an array of values. - regulated_charge — An official published charge whose rates are set by an authority: a tax, duty, levy, tariff, fee, toll, excise, or customs charge. - percentage — Percentages / ratios: percent-of, markup, discount, tax-inclusive vs exclusive, share-as-percent. - unit_conversion — Unit conversion / dimensional consistency: cm-m, kg-lb, C-F, miles-km — one canonical unit per quantity. - compound_growth — Compound growth / interest: future value, compound interest, exponential growth (the ** operator). - weighted_average — Weighted sum / weighted average / score over an array of values and weights. - eligibility — A boolean eligibility / qualification verdict derived from several criteria (and/or of conditions). - proration — Prorating / allocating an amount across a count or period (per-unit share, partial-period).

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• get_effective_schema

  Get the effective JSON Schema for a field: the static schema overlaid with LIVE meta-derived constraints (current min/max/required/…). Check this BEFORE writing a value to learn what the reactive pipeline will accept, instead of discovering an invalid mutation only by trying it and getting a schema-violation error.

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• get_field

  Get the value of a single field by its JSON Path address (e.g. "$.order.total"). Evaluates a LAZY derivation on demand.

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• get_history

  List the ISO-8601 timestamps of a model's committed mutations (most recent 100).

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• get_library

  List the JSONata functions and values a model's library exports — what an expression in this model may call, with signature, arity and originating layer. Call it before writing an expression so you reuse the model's existing vocabulary instead of re-deriving it. Returns null when the model declares no library.

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• get_model_info

  Get summary info for a model: id, version, and derivation/meta/constraint/effect counts.

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• get_spec

  Get the full stored ModelSpec JSON for a model.

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• get_state

  Get a model's merged state (base fields plus all computed derived fields). On a large model this is the biggest context cost — narrow it: pass 'paths' to project only specific subtrees (canonical addresses, each spliced back into a pruned document at its address), and/or 'depth' to cap nesting (deeper containers collapse to a '<object: N fields>' / '<array: N items>' marker). Pass an optional ISO-8601 'at' timestamp for a point-in-time read from mutation history.

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• get_view

  Evaluate a model's embedded view definition against current state and return the resolved component tree. Pass an optional 'viewId' for a named view; omit for the default view.

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• list_models

  List the ids of all currently registered Valem models (alphabetical).

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• mutate

  Apply field mutations to a model and run the reactive pipeline (derivations recompute, constraints enforce, effects dispatch). 'mutations' is a flat map keyed by canonical JSON Path address, e.g. {"$.order.qty": 3}. A ROLLBACK constraint violation returns isError with the structured list of violated constraints. Returns the actionable summary (derivedUpdated / flaggedConstraints / dispatchedEffects); pass includeTraces:true for the full derivation/constraint trace (the same payload 'explain' serves — omit it and call explain only when a value looks wrong).

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• pair_browser

  Pair this MCP session with a browser tab on the hosted Valem sandbox so both drive the same live model session. Mints a pairing on first call (or resumes an existing not-yet-approved one) and waits up to a minute for the developer to approve it. Returns {status:"paired"|"already_paired", namespaceId} once done, or {status:"pending", verificationUri, verificationUriComplete, userCode, expiresInSec} if the developer hasn't approved yet — show them verificationUriComplete when present (it already carries the confirmation code, so they only click Approve) and mention that the code on that screen should read userCode; fall back to verificationUri, which requires them to TYPE userCode. Then call this tool again (it resumes the SAME pairing, it does not mint a new one). Every other model tool (create_model, mutate, evolve_spec, get_state, explain, ...) fails with a clear error until pairing succeeds.

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• patch_model

  Apply an RFC 6902 JSON Patch document to a model and run the reactive pipeline. Unlike 'mutate' (a flat address→value map), a patch expresses array insert/remove/move and test/copy ops, e.g. [{"op":"add","path":"/order/items/-","value":{...}}, {"op":"remove","path":"/order/items/0"}]. 'path' fields use RFC 6901 JSON Pointer (slash-separated, '-' for array append), NOT the $.-rooted address form. Same result shape and ROLLBACK/schema error handling as 'mutate'.

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• restore

  Restore a model's state from a snapshot previously returned by 'snapshot' (pass it back verbatim as 'snapshot'). Overwrites the model's current base state. The snapshot must be for the same model.

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• snapshot

  Capture an immutable point-in-time snapshot of a model's state (base document + derived/meta caches). A natural safety step before a risky evolve_spec: keep the returned snapshot and, if the change goes wrong, hand it back to 'restore' to roll the state back.

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• test_spec

  Run a spec's embedded test cases (or ad-hoc given->expect cases) through the real reactive pipeline in a throwaway runtime, returning pass/fail plus per-field failures (path, expected, actual). Use this to certify domain behavior before create_model / promotion.

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• upload_blob

  Store binary content (base64-encoded in 'data') in the content-addressed blob store and get back a BlobRef {$blobId, $mediaType, $bytes} to embed in a model's binary field. Storage is content-addressed (SHA-256), so uploading identical bytes returns the same $blobId.

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• validate_spec

  Validate a ModelSpec WITHOUT creating it: returns a 'valid' flag plus structured findings (errors + warnings, each with a location and message). Use this to iterate on a draft — fix the reported errors, re-validate — before committing with create_model.

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• verify_audit

  Verify the tamper-evidence hash chain of a model's durable audit trail. Returns {valid, recordsChecked, firstBrokenSequence, detail}; a false 'valid' points at the first altered/reordered/deleted record. (Embedded mode has no hash chain and reports valid.)

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