E2E #6: the flow ordered SIE-first correctly, but the agent never discovered gnubok_create_sie_upload, ran a local preflight, and sent the user to the web wizard again; it also rendered a duplicate generic bank card before the Swedbank-specific one. 1. New sie-drop widget (ui://sie-drop/app.html), rendered definition-level by gnubok_create_sie_upload: the user drags the .se/.sie file onto the card, the widget reads the EXACT bytes (FileReader), computes sha256 (WebCrypto), calls gnubok_sie_preflight via tools/call with file_content_base64 + sha256, shows the verdict, and on Importera stages gnubok_import_sie with the preflight's mappings. No network from the iframe, no model reproduction: byte path goes through the host bridge only, narrated into chat via ui/updateContext. 2. The inline size cap now applies only WITHOUT sha256: a hash-verified payload is byte-exact by proof, so the widget's 100 KB+ base64 passes while unhashed model-retyped content stays refused. 3. Discovery + ordering fixes: create_sie_upload/preflight/import descriptions name the card path explicitly; create_company's history_note points at the card; connect_bank description says pass bank on the FIRST call when the user has named it (the duplicate generic card came from a bare call followed by the nudged retry). Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com> Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Accounted MCP server
JSON-RPC 2.0 server exposing the Accounted bookkeeping engine to MCP clients (Claude Desktop, Claude Code, etc.). Endpoint: /api/extensions/ext/mcp-server/mcp. Add ?tool_namespace=accounted for the Accounted tool names. Requests without it retain the legacy Gnubok namespace. OAuth and stdio bridges live alongside the API surface: see app/api/mcp-oauth/, packages/accounted-mcp/, and the compatibility package in packages/gnubok-mcp/.
Tool authoring contract
Enforced by tests in __tests__/: these are not style preferences, they're guard rails.
additionalProperties: falseon everyinputSchema. Guarded bystrict-schemas.test.ts. Forces clear rejections on hallucinated fields instead of silent ignores.- Descriptions ≤ 280 chars. Guarded by
output-schema.test.ts. NoArgs:/Returns:/Examples:prose: those belong in JSON Schema. Use agent-native hints ("Use to…", "Call X first", "HIGH risk"). - Staged-operation envelope for write tools:
outputSchema: STAGED_OPERATION_SCHEMA(server.ts). Fields:staged, risk_level, actor, message, preview, period_status?, next?. Thestaged: trueboolean is the explicit completion signal; agents must not infer completion from prose. Do NOT introduce a parallel{ success, shouldContinue, output }envelope. period_statusthreading: any tool that ties to a fiscal-period-bound date (categorize, mark paid, create voucher, correct/reverse entry, approve supplier invoice) passesdateForPeriodChecktostagePendingOperation. Response then includesperiod_status: { period_id, status: open|locked|closed, lock_date }so widgets and agents disable writes without round-trips.- Scope mapping: every new tool needs an entry in
lib/auth/api-keys.tsTOOL_SCOPE_MAP. Missing entries default to deny. - Tests for new write tools: add staging-gate coverage to
__tests__/voucher-tools.test.ts(or a sibling) plus executor coverage tolib/pending-operations/__tests__/voucher-executors.test.tsif the tool stages a newoperation_type.
Determinism / cache stability
Tool definitions (name, description, inputSchema, outputSchema, annotations) are declared as static object literals at module load: no timestamps, no UUIDs, no Date/Math.random in the definition layer. This makes the tools/list JSON payload byte-stable across requests, which lets agent-side prompt caches stay warm. Do not introduce per-request non-determinism into the definitions block. Anything time-bound or random belongs inside execute().
For internal Anthropic API usage (the SDK is called from lib/ai/provider.ts and lib/ai/services/anthropic-family.ts; features such as extensions/general/invoice-inbox/lib/extract-invoice-fields.ts go through getAiService() in lib/ai rather than the SDK directly): annotate stable prefixes with cache_control: { type: 'ephemeral' } and log usage.cache_read_input_tokens for hit-ratio observability. The 1h TTL from the agent-native API plan (item 10) requires the direct Anthropic API; Accounted's Bedrock path defaults to a shorter TTL.
Payload-size watchdog
payload-size.bench.test.ts enforces a tools/list JSON payload ceiling. If the test fires, the right answer is rarely "raise the ceiling". Instead, trim descriptions or set specialized wide tools to catalogVisibility: 'search'. Those tools remain discoverable with full schemas through gnubok_search_tools and callable through tools/call without bloating the default catalog.
Where things live
server.ts: the tools array + JSON-RPC dispatchertool-result.ts:withNext(),toToolError()response helpersresources/: read-onlyAccounted://URIs, registered inresources/index.ts:company/current,period/active,recent-activity,capabilities,attention,chart-of-accounts,settings/vat-treatments,booking-templates,ledger/context,reconciliation/summarywidgets/: inline HTML widgets (receipt-matcher, vat-review, pending-operations)prompts/: slash-command-style promptsskills/: domain-knowledge skill bodies served viagnubok_load_skillpublic-tools.ts: lazy authentication (issue #1814).ANONYMOUS_METHODS(initialize, ping, tools/prompts/resources listing) and the threePUBLIC_TOOLS(gnubok_search_tools,gnubok_list_skills,gnubok_load_skill) answer without credentials, rate-limited per truncated IP; every othertools/callgets a transport-level 401 +WWW-AuthenticatefromhandleMcpRequestinserver.ts, which is the challenge clients turn into their Connect prompttasks.ts: MCP Tasks extension (io.modelcontextprotocol/tasks): durable handles for long-running tool calls, rows inmcp_tasks(service-role writes only)origin-guard.ts: Origin-header validation on the Streamable HTTP endpoint (DNS-rebinding defence required by the MCP spec)staging-pii-guard.ts: refuses a plaintext personnummer in stagedpending_operationsparams/preview, so every staging tool inherits the encrypt-at-staging ruletool-namespace.ts:?tool_namespace=accountedhandling (accounted_*aliases for the canonicalgnubok_*ids)__tests__/: strictness guards + per-tool coverage