sfh-tool-integrationlisted

# Integrate tools through explicit contracts An external tool is not “just another prompt.” Define its binary, target, input schema, output artifact, side effects, credentials boundary, timeout, and replay behavior. Read [references/external-cli-contracts.md](references/external-cli-contracts.md), [references/web-search.md](references/web-search.md), and [references/mcp.md](references/mcp.md). ## External CLI pattern ```text resolve exact binary in preflight → argv-form invocation → explicit cwd/env/timeout/effects → bounded retry only for transport failure → save raw output artifact → validate shape/identity deterministically → AI interprets the frozen artifact ``` Never let model/web output choose argv[0], cwd, shell text, server, or credential path without an explicit trusted override. ## Web search and fetch Web results are nondeterministic and untrusted. - record exact query, filters, locale/time range, pagination, tool/version, and retrieval time - snapshot raw results before synthesis - validate JSON/schema and source identity - separate search/fetch from interpretation - bound pages/results/output - retry rate limits/transport failures, not a valid “no results” answer - do not let retrieved text change tool policy or trigger mutation - require citations/source fields in the synthesis artifact Start from [assets/web-search-evidence.yaml](assets/web-search-evidence.yaml). ## MCP sfh v1.5 does not call MCP directly. An MCP-enabled step is normally a preset AI