--- title: Answers from the source | daily.dev description: Tuist built an MCP server that lets customers' own coding agents answer support questions directly from the source code, docs, GitHub issues, community forum... canonical: https://daily.dev/posts/answers-from-the-source-7odaldrml twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Answers from the source | daily.dev og:description: Tuist built an MCP server that lets customers' own coding agents answer support questions directly from the source code, docs, GitHub issues, community forum... og:url: https://daily.dev/posts/answers-from-the-source-7odaldrml og:image: https://api.daily.dev/og/posts/7ODALdrMl.png og:image:alt: Answers from the source og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Answers from the source **[ Tuist ](https://daily.dev/sources/tuist-blog)** · 10 min read · 1 upvotes · 1 comments ## Summary Tuist built an MCP server that lets customers' own coding agents answer support questions directly from the source code, docs, GitHub issues, community forum threads, and release notes, rather than relying on a human support team. The system combines a Typesense-backed search index spanning docs, issues, and releases with a minimal code-reading service that lists files, greps text, and reads bounded line ranges from a pinned repo revision, with no command execution and hard-capped operations baked into the binary. A prompt (ask_tuist) orchestrates the flow, pulling vocabulary from docs, dropping into source and tests when needed, and citing pinned commit links so answers stay accurate over time. The team says this approach is only possible because their codebase is open source, and they still plan to handle questions the automated flow can't resolve, using gaps in coverage to improve documentation. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How does Tuist's selective testing decide which tests to skip? Tuist hashes each unit-test target together with its transitive dependencies via a content-hashing mechanism, then checks a server-side record of which hashes already passed on earlier runs; targets whose hash is already recorded as passing get skipped and the rest run. A hash is only recorded after a green run, so a target is skippable only if it already passed at that exact hash. UI tests are excluded from this path because they depend on the specific device they run on. _Developers comparing test-selection strategies can track how tools like Tuist explain their internals on daily.dev._ ### What tools does Tuist's MCP server expose for reading its own codebase? Tuist's MCP server exposes three code tools: search_tuist_code for finding an identifier, config key, command name, or error string; list_tuist_files for exploring a subsystem or nearby tests when the path is unknown; and read_tuist_file for pulling a specific bounded slice of code once found. A separate search_tuist tool covers docs, GitHub issues, forum threads, and release notes via a Typesense index, and everything returned is pinned to a specific commit revision. _Engineers designing their own MCP-based support tooling can follow examples like this one on daily.dev._ ### Why does Tuist expose its source code to AI agents for customer support instead of just improving its documentation? Documentation drifts from what the code actually does, while the source code never does, so an agent reading the source can verify current behavior rather than repeat stale docs. Tuist can offer this because its codebase is public; a company with a closed codebase could build the same agent-driven support internally for its own team, but could never let customers inspect the implementation the way Tuist can. _Teams weighing open source support strategies against closed-source constraints can find this kind of analysis on daily.dev._ ## Community discussion Top comments from developers on daily.dev. **@agustinbarrientos** · 0 upvotes > Try including the pinned commit and exact search query with every support answer. A developer can then reproduce why the agent chose those files ## Similar posts on daily.dev - [The new Tuist, from build toolchains to bare metal](https://daily.dev/posts/the-new-tuist-from-build-toolchains-to-bare-metal-waw3c6jvd) · Tuist · 0 upvotes · 0 comments - [What I learned building an opinionated and minimal coding agent](https://daily.dev/posts/what-i-learned-building-an-opinionated-and-minimal-coding-agent-myqj9tthj) · Hacker News · 1 upvotes · 0 comments - [Humans don't install software themselves anymore, their agents do](https://daily.dev/posts/humans-don-t-install-software-themselves-anymore-their-agents-do-lqxlw7iav) · Tigris · 0 upvotes · 0 comments --- Tags: [#ai-agents](https://daily.dev/tags/ai-agents), [#mcp](https://daily.dev/tags/mcp), [#tuist](https://daily.dev/tags/tuist) [View this post on daily.dev](https://daily.dev/posts/answers-from-the-source-7odaldrml) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Answers from the source","url":"https://daily.dev/posts/answers-from-the-source-7odaldrml","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/answers-from-the-source-7odaldrml"},"datePublished":"2026-08-23T12:23:37.487Z","dateModified":"2026-09-14T09:10:22.734Z","description":"Tuist built an MCP server that lets customers' own coding agents answer support questions directly from the source code, docs, GitHub issues, community forum...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/6531f143fcd360d7db3bbdf8ee13200b?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/6531f143fcd360d7db3bbdf8ee13200b?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"\n Tuist\n ","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"\n Tuist\n ","logo":"https://media.daily.dev/image/upload/s--3AYDH23h--/f_auto,q_auto/v1787487506/logos/tuist-blog?_a=BAMAMicg0","url":"https://daily.dev/sources/tuist-blog"},"commentCount":1,"discussionUrl":"https://daily.dev/posts/answers-from-the-source-7odaldrml","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":1},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":1}],"keywords":"ai-agents,mcp,tuist","timeRequired":"PT10M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"\n Tuist\n ","item":"https://daily.dev/sources/tuist-blog"},{"@type":"ListItem","position":3,"name":"Answers from the source"}]} {"@context":"https://schema.org","@type":"WebPage","@id":"https://daily.dev/posts/answers-from-the-source-7odaldrml","comment":[{"@type":"Comment","text":"Try including the pinned commit and exact search query with every support answer. A developer can then reproduce why the agent chose those files","datePublished":"2026-08-25T00:50:12.559Z","url":"https://daily.dev/posts/7ODALdrMl#c-g20fuzW8a","author":{"@type":"Person","name":"Agustin Barrientos","url":"https://daily.dev/agustinbarrientos","image":"https://media.daily.dev/image/upload/s--5ayxQnqn--/f_auto/v1788281802/avatars/avatar_wQYYVe5Tbj0NJ7C7qPoa8?_a=BAMAMicg0"}}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/answers-from-the-source-7odaldrml#faq","mainEntity":[{"@type":"Question","name":"How does Tuist's selective testing decide which tests to skip?","acceptedAnswer":{"@type":"Answer","text":"Tuist hashes each unit-test target together with its transitive dependencies via a content-hashing mechanism, then checks a server-side record of which hashes already passed on earlier runs; targets whose hash is already recorded as passing get skipped and the rest run. 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