https://yjtoon.yunusemrevurgun.com/blog/ Reference guides, cheat sheets, and explainers on HTTP, SQL, Unix, TOON, APIs, and LLM tooling. en Fri, 30 Oct 2026 22:53:52 +0000 https://yjtoon.yunusemrevurgun.com/blog/categories-tags-or-collections-for-reference-data/ https://yjtoon.yunusemrevurgun.com/blog/categories-tags-or-collections-for-reference-data/ Sun, 18 Oct 2026 12:00:00 +0000 How to organize reference data with one category per dataset, controlled tags and curated collections, using counts from a 205-dataset catalog. https://yjtoon.yunusemrevurgun.com/blog/clean-a-reference-dataset-before-publishing/ https://yjtoon.yunusemrevurgun.com/blog/clean-a-reference-dataset-before-publishing/ Sun, 18 Oct 2026 12:00:00 +0000 A practical checklist for cleaning a reference dataset before you publish it: check row shapes, null values, duplicate keys and label spelling. https://yjtoon.yunusemrevurgun.com/blog/api-retries-with-backoff-and-idempotency/ https://yjtoon.yunusemrevurgun.com/blog/api-retries-with-backoff-and-idempotency/ Mon, 12 Oct 2026 09:00:00 +0000 Build bounded API retries that respect Retry-After, avoid duplicate writes, and distinguish transport failures from invalid requests. https://yjtoon.yunusemrevurgun.com/blog/background-jobs-idempotency-and-the-outbox-pattern/ https://yjtoon.yunusemrevurgun.com/blog/background-jobs-idempotency-and-the-outbox-pattern/ Mon, 12 Oct 2026 09:00:00 +0000 Design retryable workers that survive duplicate delivery and crashes between database commits and event publication. https://yjtoon.yunusemrevurgun.com/blog/choose-a-probability-distribution-with-explicit-assumptions/ https://yjtoon.yunusemrevurgun.com/blog/choose-a-probability-distribution-with-explicit-assumptions/ Mon, 12 Oct 2026 09:00:00 +0000 Select a probability model by support, data-generating assumptions, and parameter conventions before fitting a familiar curve. https://yjtoon.yunusemrevurgun.com/blog/choose-sql-indexes-from-query-plans/ https://yjtoon.yunusemrevurgun.com/blog/choose-sql-indexes-from-query-plans/ Mon, 12 Oct 2026 09:00:00 +0000 Choose PostgreSQL indexes from actual filters, ordering, selectivity, and EXPLAIN output instead of indexing every column. https://yjtoon.yunusemrevurgun.com/blog/database-isolation-and-lost-updates/ https://yjtoon.yunusemrevurgun.com/blog/database-isolation-and-lost-updates/ Mon, 12 Oct 2026 09:00:00 +0000 A concurrent counter example shows why transactions alone do not prevent lost updates and when to use atomic or conditional writes. https://yjtoon.yunusemrevurgun.com/blog/evaluate-rag-retrieval-before-generation/ https://yjtoon.yunusemrevurgun.com/blog/evaluate-rag-retrieval-before-generation/ Mon, 12 Oct 2026 09:00:00 +0000 Use a judged query set to separate missing evidence, poor ranking, duplicate context, and generation errors in a RAG workflow. https://yjtoon.yunusemrevurgun.com/blog/experiment-checklist-before-trusting-a-metric-change/ https://yjtoon.yunusemrevurgun.com/blog/experiment-checklist-before-trusting-a-metric-change/ Mon, 12 Oct 2026 09:00:00 +0000 Check assignment, measurement, stopping rules, missingness, and uncertainty before treating a product metric change as causal evidence. https://yjtoon.yunusemrevurgun.com/blog/http-caching-with-etags-and-cache-control/ https://yjtoon.yunusemrevurgun.com/blog/http-caching-with-etags-and-cache-control/ Mon, 12 Oct 2026 09:00:00 +0000 A worked HTTP caching example: freshness, ETag validation, 304 responses, and a safe cache policy for public reference files. https://yjtoon.yunusemrevurgun.com/blog/keyboard-accessible-search-and-data-tables/ https://yjtoon.yunusemrevurgun.com/blog/keyboard-accessible-search-and-data-tables/ Mon, 12 Oct 2026 09:00:00 +0000 Make search dialogs and wide reference tables usable with a keyboard, narrow screens, and reduced motion. https://yjtoon.yunusemrevurgun.com/blog/llm-evaluation-checklist-for-reference-grounded-answers/ https://yjtoon.yunusemrevurgun.com/blog/llm-evaluation-checklist-for-reference-grounded-answers/ Mon, 12 Oct 2026 09:00:00 +0000 Build a practical evaluation for factual lookup, evidence coverage, abstention, and tool outcomes without trusting one aggregate score. https://yjtoon.yunusemrevurgun.com/blog/logs-metrics-and-traces-for-a-small-api/ https://yjtoon.yunusemrevurgun.com/blog/logs-metrics-and-traces-for-a-small-api/ Mon, 12 Oct 2026 09:00:00 +0000 A practical observability plan for a small API: meaningful denominators, operation IDs, latency distributions, and actionable alerts. https://yjtoon.yunusemrevurgun.com/blog/recover-git-work-without-losing-local-changes/ https://yjtoon.yunusemrevurgun.com/blog/recover-git-work-without-losing-local-changes/ Mon, 12 Oct 2026 09:00:00 +0000 Inspect, preserve, and recover commits or selected files with reflog, restore, and revert while protecting concurrent local work. https://yjtoon.yunusemrevurgun.com/blog/security-headers-without-breaking-your-site/ https://yjtoon.yunusemrevurgun.com/blog/security-headers-without-breaking-your-site/ Mon, 12 Oct 2026 09:00:00 +0000 Roll out CSP and browser security headers with a resource inventory, report-only checks, and concrete compatibility tests. https://yjtoon.yunusemrevurgun.com/blog/sql-window-functions-running-totals-and-ranks/ https://yjtoon.yunusemrevurgun.com/blog/sql-window-functions-running-totals-and-ranks/ Mon, 12 Oct 2026 09:00:00 +0000 Worked PostgreSQL examples for running totals, stable rankings, peer rows, and explicit window frames. https://yjtoon.yunusemrevurgun.com/blog/timestamps-time-zones-and-half-open-intervals/ https://yjtoon.yunusemrevurgun.com/blog/timestamps-time-zones-and-half-open-intervals/ Mon, 12 Oct 2026 09:00:00 +0000 Choose explicit timestamp units, preserve local scheduling intent, and avoid double-counting events at reporting boundaries. https://yjtoon.yunusemrevurgun.com/blog/unicode-normalization-for-search-and-identifiers/ https://yjtoon.yunusemrevurgun.com/blog/unicode-normalization-for-search-and-identifiers/ Mon, 12 Oct 2026 09:00:00 +0000 Handle composed text, accents, Turkish casing, and confusable identifiers while preserving original multilingual content. https://yjtoon.yunusemrevurgun.com/blog/validate-reference-data-with-json-schema/ https://yjtoon.yunusemrevurgun.com/blog/validate-reference-data-with-json-schema/ Mon, 12 Oct 2026 09:00:00 +0000 A small JSON Schema contract for a reference table, plus missing-field, extra-field, and semantic validation checks. https://yjtoon.yunusemrevurgun.com/blog/grok-bot-vs-muse-vs-dots-vs-openclaw-vs-hermes-ai-agents-2026/ https://yjtoon.yunusemrevurgun.com/blog/grok-bot-vs-muse-vs-dots-vs-openclaw-vs-hermes-ai-agents-2026/ Mon, 05 Oct 2026 13:30:00 +0000 Grok Bot, Meta Muse, ChatGPT Dots, OpenClaw and Hermes compared: what each agent does, rented vs owned, who it is for and what it costs. With an 8-minute film. https://yjtoon.yunusemrevurgun.com/blog/awk-sed-grep-text-processing-guide/ https://yjtoon.yunusemrevurgun.com/blog/awk-sed-grep-text-processing-guide/ Sun, 04 Oct 2026 12:00:00 +0000 awk vs sed vs grep explained with examples: search lines, edit streams, and process columns — the Unix text toolkit in one guide. https://yjtoon.yunusemrevurgun.com/blog/big-o-notation-cheat-sheet/ https://yjtoon.yunusemrevurgun.com/blog/big-o-notation-cheat-sheet/ Sun, 04 Oct 2026 12:00:00 +0000 Big O notation explained simply: O(1) to O(n!) with examples, a cheat sheet table, and tips for estimating complexity. https://yjtoon.yunusemrevurgun.com/blog/cap-theorem-explained-for-developers/ https://yjtoon.yunusemrevurgun.com/blog/cap-theorem-explained-for-developers/ Sun, 04 Oct 2026 12:00:00 +0000 CAP theorem says a distributed database can guarantee only two of consistency, availability, and partition tolerance. Learn what that means in practice. https://yjtoon.yunusemrevurgun.com/blog/cors-explained-for-api-developers/ https://yjtoon.yunusemrevurgun.com/blog/cors-explained-for-api-developers/ Sun, 04 Oct 2026 12:00:00 +0000 CORS blocks browser requests across origins unless the server allows them. Learn how preflights work and how to configure CORS headers correctly. https://yjtoon.yunusemrevurgun.com/blog/cron-jobs-explained-with-examples/ https://yjtoon.yunusemrevurgun.com/blog/cron-jobs-explained-with-examples/ Sun, 04 Oct 2026 12:00:00 +0000 Cron jobs explained: the five time fields, copy-paste schedules, crontab management, common failures, and when to upgrade to a real scheduler. https://yjtoon.yunusemrevurgun.com/blog/docker-commands-cheat-sheet/ https://yjtoon.yunusemrevurgun.com/blog/docker-commands-cheat-sheet/ Sun, 04 Oct 2026 12:00:00 +0000 Docker commands cheat sheet: run, exec, logs, build, volumes, networks, compose, and cleanup — the 20 commands behind the daily container workflow. https://yjtoon.yunusemrevurgun.com/blog/git-branching-workflows-compared/ https://yjtoon.yunusemrevurgun.com/blog/git-branching-workflows-compared/ Sun, 04 Oct 2026 12:00:00 +0000 Git branching workflows compared: GitHub Flow, Git Flow, trunk-based development, and GitLab Flow — commands, trade-offs, and which team each suits. https://yjtoon.yunusemrevurgun.com/blog/http-caching-headers-cache-control-etag/ https://yjtoon.yunusemrevurgun.com/blog/http-caching-headers-cache-control-etag/ Sun, 04 Oct 2026 12:00:00 +0000 HTTP caching headers explained: Cache-Control directives, ETag validation, Last-Modified, and strategies for APIs and static assets. https://yjtoon.yunusemrevurgun.com/blog/json-schema-validation-primer/ https://yjtoon.yunusemrevurgun.com/blog/json-schema-validation-primer/ Sun, 04 Oct 2026 12:00:00 +0000 JSON Schema validation primer: types, required fields, enums, nested objects, arrays, and how to validate payloads in any language. https://yjtoon.yunusemrevurgun.com/blog/jwt-authentication-explained-simply/ https://yjtoon.yunusemrevurgun.com/blog/jwt-authentication-explained-simply/ Sun, 04 Oct 2026 12:00:00 +0000 JWT authentication uses signed tokens so servers verify identity without sessions. Learn the header-payload-signature structure and best practices. https://yjtoon.yunusemrevurgun.com/blog/linux-file-permissions-chmod-explained/ https://yjtoon.yunusemrevurgun.com/blog/linux-file-permissions-chmod-explained/ Sun, 04 Oct 2026 12:00:00 +0000 Linux file permissions explained: reading ls -l output, octal vs symbolic chmod, ownership, setuid/setgid, and safe defaults for keys and web roots. https://yjtoon.yunusemrevurgun.com/blog/oauth2-grant-types-compared/ https://yjtoon.yunusemrevurgun.com/blog/oauth2-grant-types-compared/ Sun, 04 Oct 2026 12:00:00 +0000 OAuth2 grant types compared: authorization code, PKCE, client credentials, device flow, and implicit. Pick the right flow for your app type. https://yjtoon.yunusemrevurgun.com/blog/regex-cheat-sheet-for-developers/ https://yjtoon.yunusemrevurgun.com/blog/regex-cheat-sheet-for-developers/ Sun, 04 Oct 2026 12:00:00 +0000 Regex cheat sheet for developers: character classes, quantifiers, anchors, groups, and reusable patterns for email, URLs, dates, and logs. https://yjtoon.yunusemrevurgun.com/blog/rest-api-status-codes-which-one-to-return/ https://yjtoon.yunusemrevurgun.com/blog/rest-api-status-codes-which-one-to-return/ Sun, 04 Oct 2026 12:00:00 +0000 REST API status codes explained: when to return 200, 201, 204, 400, 401, 403, 404, 409, 422, and 500, with a rule for each case. https://yjtoon.yunusemrevurgun.com/blog/sorting-algorithms-compared-simply/ https://yjtoon.yunusemrevurgun.com/blog/sorting-algorithms-compared-simply/ Sun, 04 Oct 2026 12:00:00 +0000 Sorting algorithms compared simply: quicksort vs mergesort vs heapsort, when O(n2) sorts are fine, and what your standard library uses. https://yjtoon.yunusemrevurgun.com/blog/sql-indexes-explained-with-examples/ https://yjtoon.yunusemrevurgun.com/blog/sql-indexes-explained-with-examples/ Sun, 04 Oct 2026 12:00:00 +0000 SQL indexes speed up queries by letting the database find rows without scanning tables. Learn B-tree basics, when to index, and common pitfalls. https://yjtoon.yunusemrevurgun.com/blog/tcp-vs-udp-when-to-use-which/ https://yjtoon.yunusemrevurgun.com/blog/tcp-vs-udp-when-to-use-which/ Sun, 04 Oct 2026 12:00:00 +0000 TCP vs UDP explained: reliability vs speed, headers, handshakes, and use cases — plus a checklist for picking the right protocol. https://yjtoon.yunusemrevurgun.com/blog/twelve-factor-config-with-environment-variables/ https://yjtoon.yunusemrevurgun.com/blog/twelve-factor-config-with-environment-variables/ Sun, 04 Oct 2026 12:00:00 +0000 Twelve-factor config with environment variables: separate config from code, naming rules, secrets handling, defaults, and fail-fast validation. https://yjtoon.yunusemrevurgun.com/blog/utf8-character-encodings-explained/ https://yjtoon.yunusemrevurgun.com/blog/utf8-character-encodings-explained/ Sun, 04 Oct 2026 12:00:00 +0000 UTF-8 explained: how character encodings map bytes to text, why UTF-8 won over ASCII and Latin-1, and how to fix mojibake. https://yjtoon.yunusemrevurgun.com/blog/yaml-gotchas-for-config-files/ https://yjtoon.yunusemrevurgun.com/blog/yaml-gotchas-for-config-files/ Sun, 04 Oct 2026 12:00:00 +0000 YAML gotchas that break config files: tabs, unquoted strings, the Norway problem, anchors, multiline scalars, and how to avoid each one. https://yjtoon.yunusemrevurgun.com/blog/why-a-catalog-beats-one-big-dump/ https://yjtoon.yunusemrevurgun.com/blog/why-a-catalog-beats-one-big-dump/ Mon, 14 Sep 2026 10:00:00 +0000 One giant JSON file is easy to publish and hard to use. A catalog gives every dataset a stable URL, a readable page, and a fetch you can cache on its own. https://yjtoon.yunusemrevurgun.com/blog/http-status-codes-cheat-sheet/ https://yjtoon.yunusemrevurgun.com/blog/http-status-codes-cheat-sheet/ Mon, 14 Sep 2026 09:00:00 +0000 HTTP status codes cheat sheet: the 13 codes that matter (200, 301, 404, 429, 503...), 401 vs 403 explained, plus a fetchable API dataset. https://yjtoon.yunusemrevurgun.com/blog/bytes-tokens-and-context-windows-a-primer/ https://yjtoon.yunusemrevurgun.com/blog/bytes-tokens-and-context-windows-a-primer/ Sun, 13 Sep 2026 10:00:00 +0000 Bytes are exact and free to measure. Tokens are a model-specific estimate. Context is a budget you spend. A short primer on why the distinction matters. https://yjtoon.yunusemrevurgun.com/blog/http-methods-get-post-put-patch-delete/ https://yjtoon.yunusemrevurgun.com/blog/http-methods-get-post-put-patch-delete/ Sun, 13 Sep 2026 09:00:00 +0000 HTTP methods reference: GET, POST, PUT, PATCH, DELETE safety and idempotency table, PUT vs PATCH explained, plus a fetchable API dataset. https://yjtoon.yunusemrevurgun.com/blog/how-to-cite-open-datasets/ https://yjtoon.yunusemrevurgun.com/blog/how-to-cite-open-datasets/ Sat, 12 Sep 2026 10:00:00 +0000 CC0 data needs no attribution, so why cite it? Because a citation is how the next person finds the source when a number looks wrong. A practical format. https://yjtoon.yunusemrevurgun.com/blog/sql-join-types-inner-left-right-full/ https://yjtoon.yunusemrevurgun.com/blog/sql-join-types-inner-left-right-full/ Sat, 12 Sep 2026 09:00:00 +0000 SQL join types explained: INNER, LEFT, RIGHT, FULL OUTER, CROSS, and SELF JOIN with syntax, which rows survive, and a fetchable dataset. https://yjtoon.yunusemrevurgun.com/blog/git-commands-cheat-sheet/ https://yjtoon.yunusemrevurgun.com/blog/git-commands-cheat-sheet/ Fri, 11 Sep 2026 09:00:00 +0000 Git commands cheat sheet: the 15 essential commands (clone, add, commit, branch, merge, rebase, stash, reset) with exactly what each does. https://yjtoon.yunusemrevurgun.com/blog/unix-file-commands-cheat-sheet/ https://yjtoon.yunusemrevurgun.com/blog/unix-file-commands-cheat-sheet/ Thu, 10 Sep 2026 09:00:00 +0000 Unix file commands cheat sheet: ls, find, grep, awk, sed, tar with examples, how they compose in pipes, plus a fetchable dataset. https://yjtoon.yunusemrevurgun.com/blog/llm-glossary-key-terms/ https://yjtoon.yunusemrevurgun.com/blog/llm-glossary-key-terms/ Wed, 09 Sep 2026 09:00:00 +0000 LLM glossary: 8 key terms explained (tokens, context window, temperature, RAG, fine-tuning, quantization, KV cache, emergence) + fetchable dataset. https://yjtoon.yunusemrevurgun.com/blog/cognitive-biases-decision-checklist/ https://yjtoon.yunusemrevurgun.com/blog/cognitive-biases-decision-checklist/ Tue, 08 Sep 2026 09:00:00 +0000 Cognitive biases decision checklist: 7 biases (confirmation, anchoring, sunk cost...) with a counter-move for each, plus a fetchable dataset. https://yjtoon.yunusemrevurgun.com/blog/common-network-ports-reference/ https://yjtoon.yunusemrevurgun.com/blog/common-network-ports-reference/ Mon, 07 Sep 2026 09:00:00 +0000 Common network ports reference: 21, 22, 53, 80, 443, 3306, 5432, 6379, 8080, 27017 explained, plus how to read connection refused + dataset. https://yjtoon.yunusemrevurgun.com/blog/grounding-llm-answers-in-reference-data/ https://yjtoon.yunusemrevurgun.com/blog/grounding-llm-answers-in-reference-data/ Sun, 06 Sep 2026 10:00:00 +0000 Grounding only helps if you verify the result. A practical loop: extract each claim, look it up in the dataset, compare exactly, and fail loudly on a mismatch. https://yjtoon.yunusemrevurgun.com/blog/stop-feeding-agents-whole-datasets/ https://yjtoon.yunusemrevurgun.com/blog/stop-feeding-agents-whole-datasets/ Sat, 05 Sep 2026 10:00:00 +0000 Preloading a dataset into context wastes budget on rows the agent never reads. The lookup-first pattern fetches only the rows a task needs. Here is how it works. https://yjtoon.yunusemrevurgun.com/blog/how-a-free-data-catalog-pays-for-itself/ https://yjtoon.yunusemrevurgun.com/blog/how-a-free-data-catalog-pays-for-itself/ Thu, 03 Sep 2026 12:00:00 +0000 How YJTOON stays free: open CC0 data funded by a paid ebook companion, and why selling synthesis beats paywalling facts. https://yjtoon.yunusemrevurgun.com/blog/cutting-prompt-tokens-with-toon-a-worked-example/ https://yjtoon.yunusemrevurgun.com/blog/cutting-prompt-tokens-with-toon-a-worked-example/ Thu, 03 Sep 2026 11:00:00 +0000 A worked example: the same TCP/IP dataset in JSON (847 bytes) vs TOON (464 bytes), and how to switch formats per request. https://yjtoon.yunusemrevurgun.com/blog/open-data-for-agi-why-it-matters/ https://yjtoon.yunusemrevurgun.com/blog/open-data-for-agi-why-it-matters/ Thu, 03 Sep 2026 10:00:00 +0000 Why public, free, and open datasets — not just algorithms and compute — will decide what AGI becomes, and what builders should do about it. https://yjtoon.yunusemrevurgun.com/blog/free-public-api-on-shared-hosting/ https://yjtoon.yunusemrevurgun.com/blog/free-public-api-on-shared-hosting/ Thu, 06 Aug 2026 10:50:00 +0000 How YJTOON serves 185 datasets from a shared hosting plan: SQLite in WAL mode, IP-hash rate limiting, pre-generated static files, and no authentication. https://yjtoon.yunusemrevurgun.com/blog/prompt-caching-with-reference-data/ https://yjtoon.yunusemrevurgun.com/blog/prompt-caching-with-reference-data/ Thu, 06 Aug 2026 10:40:00 +0000 How prompt caching works with long reference data: keep stable data in a stable prefix, put variable content after it, and treat format consistency as a cache key. https://yjtoon.yunusemrevurgun.com/blog/llms-txt-and-agent-discovery/ https://yjtoon.yunusemrevurgun.com/blog/llms-txt-and-agent-discovery/ Thu, 06 Aug 2026 10:30:00 +0000 The llms.txt convention in plain terms: a simple text file at the site root that tells LLMs what the site offers and which URLs matter. How YJTOON uses it. https://yjtoon.yunusemrevurgun.com/blog/licensing-reference-data/ https://yjtoon.yunusemrevurgun.com/blog/licensing-reference-data/ Thu, 06 Aug 2026 10:20:00 +0000 What public-domain dedication (CC0) means for consumers of YJTOON data, what attribution obligations remain, and how to license reference data cleanly. https://yjtoon.yunusemrevurgun.com/blog/units-dates-and-encodings/ https://yjtoon.yunusemrevurgun.com/blog/units-dates-and-encodings/ Thu, 06 Aug 2026 10:10:00 +0000 The silent failure modes in reference data: unit names, timestamp formats, and character encodings. How YJTOON keeps them unambiguous and what consumers should check. https://yjtoon.yunusemrevurgun.com/blog/search-apis-for-agents/ https://yjtoon.yunusemrevurgun.com/blog/search-apis-for-agents/ Thu, 06 Aug 2026 10:00:00 +0000 What the YJTOON search endpoint does (minimum 2 characters, LIKE across fields, 50-result cap) and the design choices that make search usable by agents. https://yjtoon.yunusemrevurgun.com/blog/stable-identifiers-for-reference-data/ https://yjtoon.yunusemrevurgun.com/blog/stable-identifiers-for-reference-data/ Thu, 06 Aug 2026 09:50:00 +0000 Why every dataset needs a stable slug and canonical URL: caching, deduplication, versioning, and how agents should reference data they found earlier. https://yjtoon.yunusemrevurgun.com/blog/csv-vs-json-vs-toon/ https://yjtoon.yunusemrevurgun.com/blog/csv-vs-json-vs-toon/ Thu, 06 Aug 2026 09:40:00 +0000 A practical comparison of CSV, JSON, and TOON for reference datasets: token cost, parseability, nesting, and when each format is the right choice. https://yjtoon.yunusemrevurgun.com/blog/retry-after-and-backoff/ https://yjtoon.yunusemrevurgun.com/blog/retry-after-and-backoff/ Thu, 06 Aug 2026 09:30:00 +0000 How rate limiting actually works on YJTOON (120 requests per minute, escalating cooldowns) and the retry patterns agents should use when they hit a 429. https://yjtoon.yunusemrevurgun.com/blog/http-content-types-for-data-apis/ https://yjtoon.yunusemrevurgun.com/blog/http-content-types-for-data-apis/ Thu, 06 Aug 2026 09:20:00 +0000 Why the Content-Type header matters for data APIs, what YJTOON serves for each format, and how agents and browsers interpret those headers. https://yjtoon.yunusemrevurgun.com/blog/yjtoon-dataset-catalog-guide/ https://yjtoon.yunusemrevurgun.com/blog/yjtoon-dataset-catalog-guide/ Thu, 06 Aug 2026 09:10:00 +0000 A tour of the YJTOON catalog: 27 categories and 185 datasets spanning programming, HTTP, math, science, history, and more. How the catalog is organized and how to browse it efficiently. https://yjtoon.yunusemrevurgun.com/blog/agent-friendly-http-checklist/ https://yjtoon.yunusemrevurgun.com/blog/agent-friendly-http-checklist/ Thu, 06 Aug 2026 09:00:00 +0000 A practical checklist for making a public data API easy for LLM agents: stable URLs, content negotiation, clear errors, rate-limit headers, and static fallbacks. https://yjtoon.yunusemrevurgun.com/blog/a-practical-guide-to-rss-for-developers/ https://yjtoon.yunusemrevurgun.com/blog/a-practical-guide-to-rss-for-developers/ Fri, 12 Jun 2026 14:26:22 +0000 Why RSS is still the right feed format for technical blogs, and the small set of fields a developer should validate before subscribing. https://yjtoon.yunusemrevurgun.com/blog/a-quick-guide-to-open-graph-and-twitter-cards/ https://yjtoon.yunusemrevurgun.com/blog/a-quick-guide-to-open-graph-and-twitter-cards/ Fri, 12 Jun 2026 14:26:22 +0000 The minimum set of Open Graph and Twitter Card tags a technical blog post needs, why each one matters, and the easy mistakes to avoid. https://yjtoon.yunusemrevurgun.com/blog/building-a-personal-knowledge-api/ https://yjtoon.yunusemrevurgun.com/blog/building-a-personal-knowledge-api/ Fri, 12 Jun 2026 14:26:22 +0000 Why every developer should ship a small, personal knowledge API for their own use, and the minimum features it needs to be useful to an agent. https://yjtoon.yunusemrevurgun.com/blog/caching-llm-context-with-cdn-files/ https://yjtoon.yunusemrevurgun.com/blog/caching-llm-context-with-cdn-files/ Fri, 12 Jun 2026 14:26:22 +0000 Static reference files fronted by a CDN are a cheap cache for LLM context. Here is when to reach for them and how to keep them fresh. https://yjtoon.yunusemrevurgun.com/blog/choosing-tags-for-blog-posts-a-taxonomy/ https://yjtoon.yunusemrevurgun.com/blog/choosing-tags-for-blog-posts-a-taxonomy/ Fri, 12 Jun 2026 14:26:22 +0000 Tags help both humans and agents find related material. Here is the small, opinionated tag set YJTOON uses, with rules for when to add a new tag. https://yjtoon.yunusemrevurgun.com/blog/choosing-the-right-yjtoon-endpoint-for-your-agent/ https://yjtoon.yunusemrevurgun.com/blog/choosing-the-right-yjtoon-endpoint-for-your-agent/ Fri, 12 Jun 2026 14:26:22 +0000 A short decision guide for picking between the YJTOON REST API, the static file tree, and the inline JSON snippet, based on latency, freshness, and reuse. https://yjtoon.yunusemrevurgun.com/blog/closing-the-loop-on-blog-content-changes/ https://yjtoon.yunusemrevurgun.com/blog/closing-the-loop-on-blog-content-changes/ Fri, 12 Jun 2026 14:26:22 +0000 The exact 7-step workflow we use to take a blog post from a blank JSON file to a live URL on the CDN. With the failure modes and the rollback. https://yjtoon.yunusemrevurgun.com/blog/content-negotiation-with-accept-headers/ https://yjtoon.yunusemrevurgun.com/blog/content-negotiation-with-accept-headers/ Fri, 12 Jun 2026 14:26:22 +0000 How YJTOON picks between JSON, YAML, and TOON based on the Accept header, and how to override it without changing your client library. https://yjtoon.yunusemrevurgun.com/blog/designing-datasets-for-llm-consumption/ https://yjtoon.yunusemrevurgun.com/blog/designing-datasets-for-llm-consumption/ Fri, 12 Jun 2026 14:26:22 +0000 Practical rules for shaping reference datasets so they are useful to humans and to LLM agents: naming, units, ranges, ambiguity, and provenance. https://yjtoon.yunusemrevurgun.com/blog/error-handling-patterns-for-ai-agents/ https://yjtoon.yunusemrevurgun.com/blog/error-handling-patterns-for-ai-agents/ Fri, 12 Jun 2026 14:26:22 +0000 How to make agents robust to API failures without overcomplicating them. Includes retry, backoff, circuit-breakers, and graceful degradation. https://yjtoon.yunusemrevurgun.com/blog/graceful-degradation-when-an-api-is-slow/ https://yjtoon.yunusemrevurgun.com/blog/graceful-degradation-when-an-api-is-slow/ Fri, 12 Jun 2026 14:26:22 +0000 Patterns for keeping an agent responsive when a reference API is slow. Includes cached fallbacks, partial answers, and honest errors. https://yjtoon.yunusemrevurgun.com/blog/how-toon-encodes-nested-data/ https://yjtoon.yunusemrevurgun.com/blog/how-toon-encodes-nested-data/ Fri, 12 Jun 2026 14:26:22 +0000 How TOON handles nesting: objects by indentation, arrays by length-prefixed headers, uniform nested objects folded into table headers, and when it falls back to list form. https://yjtoon.yunusemrevurgun.com/blog/http-status-codes-dataset-walkthrough/ https://yjtoon.yunusemrevurgun.com/blog/http-status-codes-dataset-walkthrough/ Fri, 12 Jun 2026 14:26:22 +0000 A guided tour of one of the most-used YJTOON datasets: HTTP status codes. What is in it, what is not, and how to extend it. https://yjtoon.yunusemrevurgun.com/blog/minimal-seo-checklist-for-technical-blog-posts/ https://yjtoon.yunusemrevurgun.com/blog/minimal-seo-checklist-for-technical-blog-posts/ Fri, 12 Jun 2026 14:26:22 +0000 A short, opinionated SEO checklist for technical blog posts. No fluff, no SEO-speak. The minimum that actually moves rankings. https://yjtoon.yunusemrevurgun.com/blog/open-data-and-attribution-doing-it-right/ https://yjtoon.yunusemrevurgun.com/blog/open-data-and-attribution-doing-it-right/ Fri, 12 Jun 2026 14:26:22 +0000 How to attribute open data sources in derived datasets and in LLM prompts. A short set of rules and the small set of edge cases that trip people up. https://yjtoon.yunusemrevurgun.com/blog/prompt-engineering-for-reference-lookups/ https://yjtoon.yunusemrevurgun.com/blog/prompt-engineering-for-reference-lookups/ Fri, 12 Jun 2026 14:26:22 +0000 How to structure reference material in system prompts so models actually use it. Covers placement, length budgets, attribution, and a few anti-patterns to avoid. https://yjtoon.yunusemrevurgun.com/blog/reference-cards-in-system-prompts-a-template/ https://yjtoon.yunusemrevurgun.com/blog/reference-cards-in-system-prompts-a-template/ Fri, 12 Jun 2026 14:26:22 +0000 A copy-paste template for the "reference card" pattern in system prompts, with annotated examples and the small set of fields that actually help. https://yjtoon.yunusemrevurgun.com/blog/sitemap-best-practices-for-small-sites/ https://yjtoon.yunusemrevurgun.com/blog/sitemap-best-practices-for-small-sites/ Fri, 12 Jun 2026 14:26:22 +0000 A short checklist for keeping a sitemap.xml honest on a small site: which URLs to include, how to set lastmod, and how to avoid the common traps. https://yjtoon.yunusemrevurgun.com/blog/static-data-vs-api-endpoint-when-to-use-which/ https://yjtoon.yunusemrevurgun.com/blog/static-data-vs-api-endpoint-when-to-use-which/ Fri, 12 Jun 2026 14:26:22 +0000 YJTOON serves the same data two ways: a REST API and a CDN-fronted static file tree. Here is a decision guide with examples. https://yjtoon.yunusemrevurgun.com/blog/structured-output-vs-free-form-for-tools/ https://yjtoon.yunusemrevurgun.com/blog/structured-output-vs-free-form-for-tools/ Fri, 12 Jun 2026 14:26:22 +0000 When to force JSON-schema output and when to let the model answer in prose. A short decision guide with failure examples. https://yjtoon.yunusemrevurgun.com/blog/the-cost-of-pretty-printing-json/ https://yjtoon.yunusemrevurgun.com/blog/the-cost-of-pretty-printing-json/ Fri, 12 Jun 2026 14:26:22 +0000 How many tokens does pretty-printed JSON waste in a prompt? We measured three common styles and a couple of fixes. https://yjtoon.yunusemrevurgun.com/blog/tiny-toon-parser-in-50-lines-of-python/ https://yjtoon.yunusemrevurgun.com/blog/tiny-toon-parser-in-50-lines-of-python/ Fri, 12 Jun 2026 14:26:22 +0000 A working TOON parser in 83 lines of Python: objects, inline arrays, tabular rows, list items, and quoting. Round-trips all 185 YJTOON datasets exactly. https://yjtoon.yunusemrevurgun.com/blog/token-budgets-for-multi-document-prompts/ https://yjtoon.yunusemrevurgun.com/blog/token-budgets-for-multi-document-prompts/ Fri, 12 Jun 2026 14:26:22 +0000 A simple budgeting method for prompts that combine instructions, several reference documents, and a question. Includes a worked example. https://yjtoon.yunusemrevurgun.com/blog/toon-as-a-prompt-compression-format/ https://yjtoon.yunusemrevurgun.com/blog/toon-as-a-prompt-compression-format/ Fri, 12 Jun 2026 14:26:22 +0000 TOON is best understood as a prompt compression format, not a storage format. This reframe changes how you think about when to reach for it. https://yjtoon.yunusemrevurgun.com/blog/toon-encoder-quirks-and-edge-cases/ https://yjtoon.yunusemrevurgun.com/blog/toon-encoder-quirks-and-edge-cases/ Fri, 12 Jun 2026 14:26:22 +0000 A short tour of TOON encoder edge cases: empty cells, embedded newlines, numeric precision, and the rules for escaping safely. https://yjtoon.yunusemrevurgun.com/blog/toon-format-grammar-spec-overview/ https://yjtoon.yunusemrevurgun.com/blog/toon-format-grammar-spec-overview/ Fri, 12 Jun 2026 14:26:22 +0000 How TOON writes objects, arrays, tables, and strings: the four array forms, quoting rules, and number handling, with real output from the YJTOON encoder. https://yjtoon.yunusemrevurgun.com/blog/toon-vs-json-token-savings-measured/ https://yjtoon.yunusemrevurgun.com/blog/toon-vs-json-token-savings-measured/ Fri, 12 Jun 2026 14:26:22 +0000 Real token counts for all 185 YJTOON datasets in JSON, minified JSON, YAML, and TOON: 19% fewer tokens than minified JSON on table-shaped data, slightly more on list-shaped data. https://yjtoon.yunusemrevurgun.com/blog/understanding-rate-limit-response-headers/ https://yjtoon.yunusemrevurgun.com/blog/understanding-rate-limit-response-headers/ Fri, 12 Jun 2026 14:26:22 +0000 A reference for the rate-limit headers YJTOON returns, what each one means, and how to use them without guessing. https://yjtoon.yunusemrevurgun.com/blog/verifying-llm-output-against-reference-data/ https://yjtoon.yunusemrevurgun.com/blog/verifying-llm-output-against-reference-data/ Fri, 12 Jun 2026 14:26:22 +0000 Practical patterns for checking model answers against a small reference dataset, with code snippets and a discussion of common failure modes. https://yjtoon.yunusemrevurgun.com/blog/versioning-public-datasets-without-breaking-consumers/ https://yjtoon.yunusemrevurgun.com/blog/versioning-public-datasets-without-breaking-consumers/ Fri, 12 Jun 2026 14:26:22 +0000 How to evolve a public dataset over time without forcing every consumer to re-sync. A small set of rules learned from production. https://yjtoon.yunusemrevurgun.com/blog/when-not-to-use-a-vector-database/ https://yjtoon.yunusemrevurgun.com/blog/when-not-to-use-a-vector-database/ Fri, 12 Jun 2026 14:26:22 +0000 Vector databases are the default answer for "AI search." Most of the time they are the wrong default. Here is when to reach for something simpler. https://yjtoon.yunusemrevurgun.com/blog/why-we-keep-the-blog-system-tiny/ https://yjtoon.yunusemrevurgun.com/blog/why-we-keep-the-blog-system-tiny/ Fri, 12 Jun 2026 14:26:22 +0000 Reasoning behind YJTOON's code-only, no-admin-UI blog: durability, agent-friendliness, and the smallest surface that still works. https://yjtoon.yunusemrevurgun.com/blog/why-we-serve-data-without-authentication/ https://yjtoon.yunusemrevurgun.com/blog/why-we-serve-data-without-authentication/ Fri, 12 Jun 2026 14:26:22 +0000 Reasoning behind YJTOON's no-authentication, no-signup design and the small set of protections that make it work in practice. https://yjtoon.yunusemrevurgun.com/blog/yjtoon-api-rate-limits-and-fair-use/ https://yjtoon.yunusemrevurgun.com/blog/yjtoon-api-rate-limits-and-fair-use/ Fri, 12 Jun 2026 14:26:22 +0000 Practical guide to YJTOON rate limits, the 429 response shape, and the recommended request patterns for agents and CI pipelines. https://yjtoon.yunusemrevurgun.com/blog/using-toon-with-llms/ https://yjtoon.yunusemrevurgun.com/blog/using-toon-with-llms/ Wed, 03 Jun 2026 09:15:00 +0000 How to request YJTOON datasets in TOON format and include them in prompts with minimal token overhead. Includes practical examples and tips for agents. https://yjtoon.yunusemrevurgun.com/blog/introducing-yjtoon/ https://yjtoon.yunusemrevurgun.com/blog/introducing-yjtoon/ Mon, 01 Jun 2026 12:00:00 +0000 YJTOON provides free, structured reference datasets in JSON, YAML, and token-efficient TOON. Designed for quick human lookup and efficient LLM consumption. No signup, no limits beyond fair use.