Errors.

max_turns exhausted before completion

named bymax_turns

max_tokens_total exhausted before completion

named bymax_tokens_total

a skills: path does not resolve (file missing/unreadable at compose time)

named byskills

a skills: file is not a valid Agent Skill (frontmatter shape · missing/empty name/description)

named byagentskills

the provider reported no token usage for a priced model — every budget and ledger reads the turn as free, so the loop fails closed (R3-F1 · the usage-absence gate)

named bymodel

an assert: claims a level the evidence does not support (a StaticProof the IR cannot decide · a mis-leveled obligation · spec 15)

no permits: block declared and the body has effects — absent = zero authority (F-O8 · NEP-0003)

named bypermits

an interpolation reaches a permit bound (host · glob · program · env name) — a bound MUST be a literal, the boundary would be self-serve (F-O1 · NEP-0004 · env per NEP-0005)

an untrusted value reaches a permitted verb's argument and its canonical resolved form escapes the step's permit — re-gate refused (F-O1 · NEP-0004)

a permits env: entry names a dangerous-floor variable · the engine strips the name unconditionally, the grant can never take effect: an inert dead grant (F-O4 · NEP-0005)

named byenvpermits

a permits net.http: entry carries the *. subdomain wildcard · the grant delegates the boundary to the zone operator (every host under the suffix, present and future) — refused: name exact hosts, or the bare * when allow-all is genuinely intended (F-P5 · NEP-0008)

named bypermits

a lift: entry whose named law would not have fired on this task — a trapdoor that lifts nothing is refused, never a silent no-op (10 §the authored doors rule 6)

named bylift

builtin invoke violates its statically-checkable arg contract (e.g. nika:fetch without url: · nika:jq arg shape)

named byinvokenikanika:assertnika:chartnika:composenika:convertnika:datenika:decidenika:donenika:editnika:emitnika:fetchnika:globnika:grepnika:hashnika:image_fxnika:image_generatenika:inspectnika:jqnika:json_diffnika:json_merge_patchnika:lognika:notifynika:promptnika:readnika:tts_generatenika:uuidnika:validatenika:waitnika:write

nika:done invoked outside an agent: loop

named byagentnikanika:done

task cancelled (workflow failure gate · user cancellation)

named byworkflow

invoke.workflow: target is not statically resolvable (templated · malformed · unpinned registry ref) — a call graph you cannot draw before the run cannot be bounded (spec 14)

named byinvokeworkflow

the child workflow's effect boundary exceeds the parent capped by the call-site declaration (Authority(child) subset of Authority(parent) intersect declared · spec 14 laws 3/4)

named byworkflow

the static call graph is not acyclic (self-launch · cycle · spec 14 law 7 · NIKA-SEC-003 is the runtime depth backstop)

the typed call does not compose — parent args do not fit child inputs, or child outputs do not fit parent returns (spec 14 law 2)

named byinputsoutputsreturns

cycle in the precedence graph G_p = E_d ∪ E_c (incl. self-dependency · via with:/after:)

named byafterwith

with:/after: references an undeclared task

named byafterwith

on_error.recover references a task downstream of the declaring task (await would deadlock)

named byon_errorrecover

after: predicate outside the closed set (success · failure · skipped · terminal)

named byafter

statically dead task — an incoming edge's pass-set excludes every reachable producer state, or the when: gate is false under every reachable upstream combination (gate algebra v2)

named bywhen

status compared against a literal outside the vocabulary (success · failure · skipped · cancelled) — == never matches, != always holds

a group.<name> fold names a group no task declares — including a bare group and the group a renamed member left empty

named bygroup

an unwind task declares group: — cleanup never enters G_p, so it cannot be a fan-in member

named bygroup

the decision bundle is malformed or violates its own laws (float weight · undeclared evidence key in rules · identity key feeding a technical dimension · missing contradictory fixture · monotonicity violated by the bundle's own fixtures) (spec 11)

the evidence snapshot does not satisfy the bundle's evidence schema (type misfit · unauthorized source · integrity below the declared floor · undeclared key) (spec 11)

named byschema

a declared inputs default or typed const value does not conform to its declared type (R3b · LAW-TYPE-0211)

named byconstinputs

declared-but-unused — a vars:/env:/secrets: name or a permits: entry (exec program · tool glob · net host · fs path) that nothing in the body references (advisory check hint · never fails the audit — the reverse direction, used-but-undeclared, is the hard NIKA-VAR-001/NIKA-DAG-002/NIKA-SEC-004 surface)

named byenvpermitssecrets

non-zero exit code (default capture modes)

named bycapture

spawn failure (command not found · permission)

named bycommand

provider call failed (HTTP error · provider refusal)

written aboutThe agent workflow spectrum

structured output failed schema validation (after any engine-internal retries)

named byafterschema

the provider reported no token usage for a priced model — the ledger cannot bill the call honestly (fail-closed · R3-F1)

named bymodel

the provider spent tokens yet the visible answer is empty — a thinking model ate the budget on its reasoning trace (fail-closed · #651 · raise max_tokens or use a no-think variant)

named bymax_tokensmodelthinking

unknown tool (unresolvable nika:/mcp: id)

named bynika

tool args failed the tool's schema

named byschema

a dependency resolved that nika.lock does not pin, or a hand-edited lock digest does not match (pin-by-default · the lock's own hash catches the edit · spec 15)

named bynika

MCP server not configured / not reachable at call time

MCP tool call failed (transport · tool-side error)

the YAML itself does not parse (syntax error)

missing envelope field (nika: / non-empty tasks:)

named bynikatasks

nika: is not a kebab-case id (^[a-z][a-z0-9-]*$)

named bynika

workflow: id violates ^[a-z][a-z0-9-]*$

named byworkflow

unknown field — strict mode rejects anything outside the closed v1 set

task id violates ^[a-z][a-z0-9_]*$ (snake_case · CEL-safe · no hyphens)

duplicate task id within the workflow

named byworkflow

task declares no verb — exactly one of infer/exec/invoke/agent required

named byagentinferinvoke

task declares multiple verbs — exactly one required

timeout: violates the quoted Go-duration contract (positive · max 24h · descending units)

named bytimeout

retry: block violates the spec shape

named byretry

on_error: block violates the spec shape (fields mutually exclusive)

named byon_error

with:/extract: binding uses a reserved name (output · status · error · started_at · ended_at · duration_ms)

named byextractwith

secrets: entry is not a store reference — inline literals forbidden

named bysecrets

duplicate mapping key — no silent last-wins

missing required field in a verb body (infer.prompt · exec.command · invoke.tool)

named bycommandexecinferinvokeprompt

generic structural validation — wrong YAML shape for a field

tasks: is a sequence — it became a map keyed by task id (drop `- id:`, the key IS the identity)

named bytasks

a task carries an id: field — the map key is the identity, the field is gone

a task carries depends_on: — dead since W2 (data → with: bindings · control → after: predicates · check --fix migrates)

named byafterwith

decode: with capture: structured — that capture already IS an object · type it with returns:

named bycapturedecodereturns

a declared entropy x clock contradiction · entropy: ambient paired with clock: virtual — the ambient declaration contradicts the determinism demand (NEP-0010 · F-P3)

a declared entropy x clock contradiction · entropy: none | seeded paired with clock: system — deterministic journals cannot ride the wall clock (NEP-0010 · F-P3)

named bysystem

entropy: none declares strict determinism while a structural randomness source is consumed (a live retry jitter · nika:uuid) — the strict declaration cannot hold (NEP-0010 · F-P3 · judged at check)

named byjitternikaretry

a gateway artifact (deployment bundle · capabilities report · lowering report · fidelity report · authority delta) is malformed or violates its laws (unknown promoted · permissive_unsafe without refusal · disclosure subset-chain violated · child authority exceeding parent) (spec 12)

policy lowering is permissive_unsafe — the backend would allow what the policy forbids · refused with the divergence witness (spec 12)

exec refused before the child spawns — either the shell floor (a destructive/privilege pattern · always-on · independent of permits:) or the mock plane under `nika test`, which refuses EVERY command by design (it simulates the model, not effects) · under test the exit is `nika run` for real effects, or an `on_error: recover` rehearsal on the task

named bycommandmodelon_errorpermitsrecovershell

agent tool call outside the tools: whitelist

named byagenttools

run-recursion bound — nested-run depth exceeded OR self-launching workflow

named byworkflow

effect outside the declared permits: capability boundary (fs/net/exec/tool)

named bypermits

written aboutThe blast radius is part of the file

SSRF block — a nika:fetch/nika:notify URL resolves to a loopback/private/link-local/metadata target (always-on engine floor · independent of permits:)

named bynikapermits

secret flow — a secrets.<name> value reaches an unsanctioned sink (exec argument · invoke payload · infer/agent prompt) · the diagnostic carries the taint path + the egress clause that would sanction it (spec 10 · flow rules in 01 §egress)

named byagentinferinvokepromptsecrets

secret egress — a tainted value reaches the workflow boundary (outputs:) · the diagnostic carries the taint path (spec 10 · the to: outputs sanction in 01 §egress)

named byoutputsworkflow

data-as-code sink · a nika:fetch resolved URL path names a code-bearing class (serialized-executable · script/interpreter · executable binary/module · the closed NEP-0006 list) and the task declares no door — no lift: entry naming the data-as-code law · the read hides an execution sink (F-O7 · NEP-0006)

named byliftnika

lethal trifecta complete — the declared boundary grants private read (fs.read non-empty) + untrusted ingress (a nika:fetch builtin invoked · an mcp:* tool invoked · an agent: whose whitelist admits ingress) + external egress (net.http non-empty · an escaping fs.write glob · exec enabled), the untrusted content REACHES an egress-capable task's effect surface (a realized flow), and no blocking invoke: nika:prompt (no default:) dominates it (NEP-0002 v2.0 · the Rule of Two as a static check)

named byagentinvokenikaprompt

the approval-capability law is violated · a rate-limited approval burst (the N+1th distinct mint of a run) · an approval whose resolved content hash differs from the shown hash (content_mismatch) · a ticket replayed across runs or steps (scope_mismatch) · or the static heterogeneous-batch refusal (one prompt unleashing two or more effect classes) — the 6th invariant (NEP-0013 · F-P4)

named byprompt

preview-commit divergence — the commit digest recomputed at the sink over the exact bytes about to fire differs from the preview digest computed at resolution (one bit of rendered argv · a permuted context field · a mutated tool argument) · the step refuses fail-closed and the receipt carries divergence:{preview, commit} — judged = executed at the action scale (NEP-0015 · F-P6)

unordered shared writes — two tasks incomparable in the DAG closure whose literal nika:write/nika:edit paths collide with no ordering edge (after: · with:) to serialize them, or a for_each fan writing one constant path · parallelism is safe exactly where the writes are provably disjoint (NEP-0014 law 1 · F-P15)

named byafterfor_eachnikataskswith

the affirmative-consent law — a confirm-mode human gate (invoke: nika:prompt · mode absent or confirm) reaches an egress-capable task over a route no affirmative gate closes: a REFUSED confirm settles success with value false, so a bare after: { gate: success } edge, a when: that never reads the answer, and a when: provably true on the refusal all let the effect through · the gate is credited only when every route consumes the answer and proves false on it (the Kleene-falsifiable when: · when: false · a closer confirm gate owns its closure) · an undecidable gate (a nested binding · a non-fragment expression) defers to the advisory hint, never a refusal (NEP-0020 · P0-2 of the 2026-07-30 audit)

named byafterinvokenikapromptwhen

the order law — an exec: task sits transitively downstream of a net-effecting task (nika:fetch · nika:notify) over the derived graph (with: data edges ∪ after: control edges) · content the workflow did not author must not reach a shell · UNCONDITIONAL: no block declares it and none can disable it

named byafterexecnikashellwithworkflow

task (or for_each iteration) exceeded timeout:

named byfor_eachtimeout

unknown type name (in types: · returns: · an outputs: type) — did-you-mean when close

named byoutputsreturns

returns: and schema: on the same task — one contract, one spelling

named byreturnsschema

returns: type unreachable from the declared decode: (an object contract over decode: text · …)

named bydecodereturns

a secret-carrying type in a lowered position (reserved with secret<T> · W4)

regex pattern outside the locked dialect (backreference · lookaround · named group · inline flags · lazy/possessive · word-boundary · unicode-class — spec 09 §the regex dialect)

named bygroup

run-time contract violation — the decoded value does not fit returns: (exec:/invoke: lane)

named byexecinvokereturns

vars: is a dead envelope field (R3a · the E-split)

env: is a dead envelope field (R3a · the E-split)

named byenv

a value-namespace read outside the three-authority family (R3a · LAW-SURFACE-0201)

unresolved reference (unknown namespace entry · undeclared inputs/const/secrets/with key)

named byconstinputssecrets

binding cardinality — a jq binding emitted zero or multiple values

provably-invalid path into a declared schema (static walk)

named byschema

jq runtime error while evaluating a binding

static expression violation — outside cel-subset/0.1 · chained relation · unknown function · non-boolean when: root · jq compile error

named bywhen

expression type error at evaluation — cross-type compare · non-boolean when: value · for_each over a non-array

named byfor_eachwhen

bytes value substituted into a string position

unclosed ${{ opener

typed outputs value did not match its declared type: at run end (the output half of the callable contract)

named byoutputs

bare tasks.X is the envelope, not a value — the projection set (.output/.status/.error/.duration_ms) is closed and required (04 §namespaces · 0.103 · #75 D2)

named bytasks

a tasks.* reference outside the boundary (with: · after: · on_error.recover · an unwind task reading its producer · workflow outputs) — hoist it into with: (check --fix applies it)

named byafteron_erroroutputsrecovertaskswithworkflow