UNIDROIT Principles 2016
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UNIDROIT Principles 2016 as executable rules: closed questions answered with grounds and source text
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TDQS
Scored across 21 tools
Several clusters are genuinely confusable: law_ask / law_case_ask / law_query / law_screen all sound like 'ask a legal question', and law_explain / law_inspect / law_argue all sound like 'analyse an answer'. The descriptions do attempt to draw hard boundaries (discovery vs answer, structural query vs case, prepared vs published vs captured), but the distinctions only become clear after reading long walls of text, so misselection risk is real. A handful of tools (law_sources, law_packages, law_search, law_revoke_answer) are cleanly distinct.
Every tool is snake_case with the same `law_` prefix and a verb or verb_noun stem (law_ask, law_search, law_publish_answer, law_revoke_answer). No camelCase or bare nouns break the pattern, and related operations share suffixes predictably (_answer, _process, _rules).
21 tools is heavy and sits in the borderline band; the domain (formalised law engine with proofs, editions, processes, publication) does justify breadth, but tools like law_passport, law_answer_capabilities and law_capture_answer feel like internal/administrative surface an agent rarely needs. The publishing trio (prepare/capture/publish/revoke) could arguably be collapsed.
The lifecycle is unusually well covered: discovery (search/packages/rules/sources), evaluation (ask/case_ask/argue/query/screen), process simulation, explanation, inspection, editions, and a full prepare→publish→revoke pipeline plus a divergence-reporting path. Minor gaps: no explicit tool for deleting/cleanup of prepared documents beyond 24h expiry, and no capability-discovery for which instruments support deadlines or positions without probing.
Available Tools
21 toolslaw_answer_capabilitiesARead-onlyInspect
A machine-readable matrix of the Lens producers that are actually installed, of replay/projection checks, profiles, limits and the contract tests that confirm them. declared_only means a schema with no executable witness.
law_argueARead-onlyInspect
How robust a conclusion is: the map of the dispute under the argumentation profile The answer falls into four classes: SKEPTICALLY_ACCEPTED — the conclusion is invulnerable (it survives in the grounded extension); CREDULOUSLY_ACCEPTED — merely defensible (there is a position for it and a position against); REJECTED — it survives nowhere; NO_ARGUMENT — there are no arguments at all. It builds ALL arguments out of the facts and the rules of the instrument (chains that did not fire in ordinary inference included), the rebut/undermine/undercut attacks and the defeats by priority. Predicate names come from law_packages. On large instruments a refusal by cap is possible — narrow facts or raise limits.maxArguments.
Inputs: predicate (required), args, facts, limits, +3 more.
law_askARead-onlyInspect
Put a question to formalised law. When the answer is "not established" it carries whyNot — the engine's why_not report: the candidate rules and the state of every conjunct (satisfied / not satisfied / undetermined); the missing facts are visible there and need not be guessed. BEFORE THE FIRST call obtain the predicate names through law_search (a question in your own words → addresses) or law_packages (the signatures of a known instrument) — an invented name will be rejected. If the tool returned an error or "not established", THAT IS THE ANSWER: pass it to the user and do not substitute general knowledge about the law of some other country. But "I found no suitable instrument" is NOT an answer until law_search has been asked: silence of the catalogue is a property of searching by title, not a conclusion about the corpus. kind='truth' — whether a fact is established; kind='collect' — enumerate the records; kind='deadline' — compute a time limit on the official calendar; kind='positions' — which DUTIES arose from the facts and what their statuses are; kind='why_not' — the why_not report on the same goal, whatever the status of the answer. The answer carries the rules applied, the warnings and the provenance with hashes; truth/collect also carry a signature block for presentation. The server does not guess: where a norm is not formalised, the answer is "not established" or an error.
Inputs: args, calc, days, kind, +18 more.
law_capture_answerCRead-onlyInspect
Run a registered producer and obtain producerControl/0.2 for a later verifiable preparation of a Lens. The producer is chosen only from the shipped registry.
Inputs: request (required), producer (required).
law_case_askARead-onlyInspect
The ask operation: run a registered case of a case package over its pinned dependencies and return the answer: by default a projection of the evaluation document without the proof graph, on responseMode full or proof: true the canonical document with a proof and a manifest. The question is JSON per query.schema.json (query), an evaluate string (evaluate + queryId), a saved queryId without query, or card + args. A refusal to prepare is an error with an LDC-* code, never an empty answer.
Inputs: package (required), args, card, case, +5 more.
law_editionsARead-onlyInspect
The axis of editions (O-2): what changed in an instrument between two dates of the law — the state of the editions, the dating of the norms and the semantic diff between the D1 projections. The verdict NOT_DATED means "there was nothing to date it by", not "nothing changed". The outcome of a particular question on a date comes from law_ask with legalTime.
Inputs: dateA (required), dateB (required), package (required).
law_explainARead-onlyInspect
Unfold the proof of a law_ask answer into a chain "rule ← premises → conclusion". The compact input: question (the original law_ask arguments, truth/collect), resultHash and codeHash from the provenance of the answer. The server repeats the computation and compares the hashes; if anything changed it refuses explicitly. Alternatively pass the evaluation from law_ask(proof=true). answerResource=fullAnswer.uri explains a stored compact snapshot without recomputing and without the client loading pages; by default only the proofRef chain. nodeId selects one node and all of its premises (up to 24 KB, otherwise an explicit refusal). proofHash refers to the whole graph; scope marks the part selected.
Inputs: nodeId, codeHash, question, evaluation, +2 more. Returns: steps, proofHash
law_inspectARead-onlyIdempotentInspect
Evaluation inspector over a SAVED evaluation document: summary — the origin card, resultHash and snapshot verification, listings of results, positions and issues; slice — the closure of proof nodes for a query, rule, position or node with addresses, both sides of BOTH, defeats, values, names resolved against the snapshot; diff — what changed between two documents on the context, result and justification levels; locate — the declaration by StableId. Nothing is evaluated or recomputed: the source is evaluation from law_ask(proof=true) or an answerResource. Missing data is a limit state (limits), never a negation.
Inputs: operation (required), page, index, bundle, +7 more. Returns: object
law_packagesARead-onlyInspect
The catalogue of formalised law: instruments, predicates with signatures, the boundaries of coverage. This is where the NAMES of predicates come from — they must never be guessed. But do NOT start from the catalogue when looking for the right instrument: the overview is large, and the title of an instrument rarely matches the words of a question ("Newton's laws of motion" contains no word "physics"). A question in your own words goes to law_search first, which returns addresses; the catalogue is for the exact signature of what you found. With no arguments — the overview: one line per instrument (key, title, legal order, counters of rules, facts, signatures, norms, constants); a whole instrument — package="kz-gpk"; a search over the signatures, labels and constants of every instrument — query="substring". All three modes are PAGED: limit and offset, with the remainder named in the text (showing a–b of N; k more) and in structuredContent (total, truncated, next — a ready-made continuation call). The unit of a page is named by pageUnit: the overview and query page over INSTRUMENTS (20 and 20 by default), package=… pages over the SIGNATURES of one instrument (20 by default, 300 at most) — large codes carry thousands. package=… together with catalog=… pages a separate list of the instrument: "questions" — the CATALOGUE OF QUESTIONS: which enquiries are provided for (a question in words, a form, a predicate or norms) and what the instrument does NOT answer, with the type of reason; a card is a template of an enquiry, not an answer, and not every instrument has one; "norms" — the NORMS of the instrument, "constants" — the CONSTANTS (names of declarations). "task-guides" — TASK GUIDES: the order of applying a canon to a document — what to gather, which cards to ask and how to read the answers; a guide answers nothing. catalog="task-guides" is allowed without package too — every guide of the profile; guide=… — the detail of one guide; the walkthrough — MCP Prompts under the same name. The detail of an instrument prints a preview of these lists and names the count and the ready-made call for the mode.
Inputs: guide, limit, query, offset, +2 more.
law_passportBRead-onlyInspect
Passport of an exact release: purpose, interface, boundaries, checks and performance. The reports section holds the history of measurements, failures included. Entries are paged by JSON Pointer; next continues the answer.
Inputs: name (required), version (required), contentHash (required), index, +3 more.
law_prepare_answerBInspect
At the explicit request of the user, repeat between 1 and 12 earlier law_ask or law_process_run calls, compare their replayControl strictly, and prepare a non-public frozen document for 24 hours. The client never supplies the machine answer: the server obtains it only by executing afresh. A divergence in any input, in the law, in a resource, in the server code, in the engine library or in the result rejects the document as a whole.
Inputs: question (required), language, assistant, calculations, +2 more. Returns: expiresAt, previewUrl, contentHash, resultCount, +3 more
law_processARead-onlyInspect
Which stages the procedure established by an instrument consists of, and whether it carries a structural defect. The stages, the transitions and the condition of every transition are reconstructed from the formalisation rather than retold: what leads from where to where, and under what condition. The check of the graph: unreachable stages, dead transitions, a transition that enters no stage at all. Without package — the list of instruments whose procedure is formalised. A stage with no exit is named but is NOT counted as a defect: whether it is terminal by design cannot be seen from the formalisation.
Inputs: package.
law_process_runBRead-onlyInspect
How a particular case will run, step by step: a log of {date, attempt?, facts?} is executed frame by frame, and the law of each frame is the law of ITS date. The answer says: which stages have been entered; which attempted transition produced NO legal effect; which duties are violated and which time limits are running; what is available next and WHAT EXACTLY is missing for the rest. The names of transitions come from law_process. Stages entered means "was it ever entered", not "where it is now": the core 0.1 does not compute points of the current state.
Inputs: steps (required), package (required), instance (required), legalTime, +2 more.
law_publish_answerAIdempotentInspect
Publish a prepared document. Repeating it with the same preparationId idempotently returns the same URL and the same separate revocation secret.
Inputs: preparationId (required). Returns: revoked, publicId, publicUrl, publishedAt, +1 more
law_queryARead-onlyInspect
A deterministic LawQL query over the CLIR of a formalization: a question about the model of the act itself, not about a case. Relations (14): anchors, edges, fields, imports, interpretations, labels, links, literals, nodes, norms, positions, rules, variables, windows. Full field lists: law query --schema. Functions (9): anchor/1, labels/1..2, short/1, contains/2, overlaps/2, starts_with/2, ends_with/2, position/2, derivation/2. exists/not exists over a bound variable; equality and membership only, no arithmetic and no ordering comparisons. Scope: corpus by package.name (for example kz.corpus.labour_code, not a file name) or a glob; without corpus, the whole profile slice; a scope outside the profile is empty (CORPUS_EMPTY). Examples: from r in rules where r.head_predicate == "urn:…#eligible" select r.id as producer, r.strength as strength, anchor(r.id) as anchors — who produces; from l in literals where l.predicate == "urn:…#eligible" select l.node as reader, l.context as context — who reads; query eligible over "pkg" { for x: Person; where applicant(x); select eligible(x); } — inference by the core. This is orchestration over the CLIR and the core; no new legal semantics is implemented here. Instead of text, a question from the catalog with arguments: anchors-of, imports-of, links-of, producers, readers, type-step (see law query --list for the set) (predicate/node/type parameters are URNs, pkg is a package.name or a glob). A structural answer is a queryPage: resultHash of the full queryResult, snapshot (hash of the scope package list), rowCount, rows by rowLimit (20, at most 5000) and rowOffset, next with the snapshot for continuation; full: true returns the full queryResult when the scope is one package. Every row carries provenance (CLIR nodes); an empty answer carries the explain funnel (emptyAt names the clause); errors carry LDC-Qxxxx codes with hints; a source product too wide is refused before execution (QUERY_TOO_BROAD), a continuation on another snapshot as SNAPSHOT_CHANGED.
Inputs: case, full, limit, query, +7 more.
law_reportARead-onlyInspect
A REPORT of a divergence between the formalisation and the source: the answer contradicts the pinned text, a norm of the source is not expressed by a rule, a label diverges from the text, an address cannot be found. A report is a hypothesis for triage by a formaliser: it does NOT change the law, it never reaches the answers of the other tools, and "not derived" does not become "derived" because of it. An address is required and is checked against the catalogue: package, fragment (a StableId from law_sources) and/or predicate; callId is the X-Law-Call-Id of the answer you disagree with. The entry goes into the server log.
Inputs: package (required), category (required), expected (required), observed (required), +3 more.
law_revoke_answerADestructiveIdempotentInspect
Revoke a published document using its separate secret. The public id alone grants no control; revocation closes the HTML page, the API and the download.
Inputs: publicId (required), revokeSecret (required). Returns: revoked, publicId
law_rulesARead-onlyInspect
The rules of formalised law put into words: exactly how a predicate is derived (premises, source articles). Call this BEFORE supplying facts to law_ask — the rules say which facts are needed instead of leaving them to be guessed. For large instruments package=… returns a table of contents; the full text comes from predicate=…. The listing by package is paged: limit (20 by default, 500 at most) and offset; the remainder is named in the text (showing a–b of N; k more) and in structuredContent (total, truncated, next — a ready-made continuation call).
Inputs: lang, limit, offset, package, +4 more. Returns: next, limit, rules, total, +8 more
law_screenARead-onlyInspect
Build a necessary condition — a superset — for the preliminary selection of rows from an external source. This is NOT a legal answer and NOT SQL: the result is a typed tree and a manifest of the extensions up to TRUE. Every row that passes must then be computed in full by the engine, with a proof graph, on the same snapshot of the data. The binding is passed as a pinnable object; sourceSchemaContentHash is the actual hash of the source schema and is compared loudly with the pin. Case facts that carry provenance (origin, document, quote, extractor) are supplied to law_ask, not here. The confidence figure is read by the package EvidencePolicy, not by this tool and not by the engine.
Inputs: goal (required), binding (required), package (required), sourceSchemaContentHash (required), +1 more. Returns: manifest, condition, disclaimer, schemaVersion
law_searchARead-onlyInspect
A semantic SEARCH over formalised law: a question or a notion in your own words → candidates with addresses — predicates with signatures, rules, article fragments. This is the layer of DISCOVERY, not of the answer: the result says WHAT to ask next (law_ask by signature, law_rules, law_sources) and establishes neither a fact nor a norm. The ranking is a deterministic lexical embedder, and similarity of text is not applicability of a norm. If you know the exact name, go straight to law_packages/law_ask; an empty result does NOT mean the norm does not exist.
Inputs: query (required), kinds, limit, package. Returns: model, query, fallback, candidates, +3 more
law_sourcesARead-onlyInspect
Sources: by default short excerpts (view=summary), 5 texts per page, with the address of the full text in fragments[].full. Either package or fragment is required (a StableId from law_search/law_rules). view=full returns exact parts of the text: textRange sets a range of Unicode characters, fragments[].next is the continuation with a contentHash. The hash refers to the WHOLE source, not to the excerpt or the part. textOffset/textLimit require fragment; a continuation requires contentHash. Lists are paged with offset/limit; the answer budget may shrink a page.
Inputs: view, limit, offset, status, +6 more.
Tool Schema Changelog
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