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What’s New

Recent changes to the Encyclopedia.

2026-04-06 (late night)

What’s New

  • New article: Approval Fatigue – when approval requests come faster than a human can genuinely evaluate them, oversight degrades into rubber-stamping.
  • New article: Shadow Agent – an AI agent operating inside your organization without anyone in governance knowing it exists.
  • New article: Tool Poisoning – malicious tool descriptions that hijack agent behavior through the tool discovery channel.
  • New article: Big Ball of Mud – the most common software architecture in practice: a haphazardly structured, sprawling, duct-taped system that resists all attempts at understanding.
  • New article: Premature Optimization – spending effort to make code faster before you know where the bottleneck is, trading clarity for speed that nobody needed.
  • New article: Technical Debt – the accumulated cost of shortcuts, deferred maintenance, and expedient decisions that make future changes harder and slower.
  • Visual: Antipattern articles now display a distinctive red prohibition sign admonishment, distinguishing them from patterns (green checkmark) and concepts (blue info icon).
  • Improved: Local graph widget now shows inverted labels for incoming edges, making relationship direction clearer.
  • Cross-references: Added reciprocal Related Patterns links across 30 existing articles connecting them to the six new antipatterns.

Metrics

  • Total articles: 165
  • Coverage: 165 of 206 proposed concepts written (80%)
  • Articles edited since last deploy: 37 (6 new antipatterns + 30 reciprocal link updates + 1 graph fix)

2026-04-06 (evening)

What’s New

  • New feature: Pattern Map – an interactive force-directed knowledge graph showing all 159 articles and 893 connections. Search, zoom, hover to highlight connections, drag to rearrange, click to navigate. Every article page now has a local graph widget below the type marker showing its immediate neighbors.
  • New article: Team Cognitive Load – how the mental effort of understanding and maintaining systems limits what teams and agents can effectively own.
  • New article: Ralph Wiggum Loop – the embarrassingly simple pattern of restarting an agent with fresh context after each unit of work, using a plan file instead of an orchestration framework.
  • New article: Happy Path – the default scenario where everything works, and why recognizing it is the first step toward building software that handles the real world.
  • Improved: The Checkpoint article gained coverage of ephemeral environments as a checkpoint strategy. The Bounded Autonomy article now covers dynamic trust-score de-escalation. The Model article now covers reasoning capabilities, multimodal input, and model selection guidance. The MCP article now covers Linux Foundation governance, Streamable HTTP transport, and OAuth 2.1 authentication.
  • Sources: Added intellectual lineage to the Code Smell, Agent, and AI Smell articles.
  • Infrastructure: Social preview images for link sharing, external links open in new tabs, site now indexable by search engines, sitemap live for crawlers.
  • Other: Updated the Meta Report with the engine’s eighth self-evaluation.

Metrics

  • Total articles: 159
  • Coverage: 159 of 191 proposed concepts written (83%)
  • Articles edited since last deploy: 15 (3 new articles + 4 targeted edits + 3 sources audits + 5 infrastructure)

2026-04-06 (morning)

What’s New

  • New article: Ralph Wiggum Loop – the embarrassingly simple pattern of restarting an agent with fresh context after each unit of work, using a plan file instead of an orchestration framework.
  • New article: Agent Teams – how multiple AI agents coordinate through shared task lists and peer messaging, scaling agentic work beyond what one human can direct.
  • New article: Externalized State – how to store an agent’s plan, progress, and intermediate results in files so workflows survive interruptions and stay auditable.
  • New article: Logging – how to record what your software does as it runs, covering structured logs, severity levels, and why logging is the primary way both humans and AI agents understand runtime behavior.
  • New article: Happy Path – the default scenario where everything works, and why recognizing it is the first step toward building software that handles the real world.
  • Improved: The Context Engineering article now covers four named operations (select, compress, order, isolate), signal-to-noise framing, and production-scale concerns like cache efficiency.
  • Improved: The MCP article now covers current governance (Linux Foundation), Streamable HTTP transport, OAuth 2.1 authentication, security threats, and adoption metrics.
  • Improved: The Model article now covers reasoning capabilities, multimodal input, model selection guidance, and intellectual sources.
  • Improved: The Subagent article gained three named use case categories (exploration, parallel processing, specialist roles), a warning against overuse, and guidance on using cheaper models for subagent tasks.
  • Improved: The Agent article gained cross-section links to Least Privilege, Boundary, and Test, connecting the book’s central agentic concept to foundational patterns.
  • Improved: The AI Smell article gained a new section on agent struggle as a code quality signal – when your agent fails repeatedly, the problem may be your code, not the agent.
  • Improved: The Steering Loop article gained tighter prose, a new section on completion gates, and proper source attribution.
  • Improved: The Bounded Autonomy article gained tighter prose and added coverage of dynamic trust-score de-escalation.
  • Improved: The Checkpoint, Design Doc, Architecture Decision Record, and Conway’s Law articles received prose quality improvements.
  • Improved: Added intellectual lineage to the Crossing the Chasm and Skill articles.
  • Other: Updated the Meta Report with the engine’s seventh self-evaluation: both previous hypotheses confirmed, coverage velocity doubled, and the new stochastic selection system shows early promise.

Metrics

  • Total articles: 165
  • Coverage: 165 of 200 proposed concepts written (83%)
  • Articles edited since last deploy: 19 (5 new articles + 12 targeted edits + 2 sources audits)

2026-04-06

What’s New

  • New article: Checkpoint – how to insert verification gates into agentic workflows so agents catch errors at each stage instead of building on broken foundations.
  • New article: Architecture Decision Record – how to capture design decisions so future readers (human or AI) don’t have to guess why the system is built this way.
  • Improved: Every article now displays a visual marker identifying it as either a Pattern (a solution you can apply) or a Concept (an idea to recognize and understand), helping readers orient instantly.
  • Improved: The Feedback Sensor article received tighter prose, a new Sources section, and stronger motivation for why automated checks matter.
  • Improved: Added a Sources section to the Memory article, tracing the concept’s origins from cognitive psychology through modern AI agent memory systems.
  • Other: Updated the Meta Report with the engine’s sixth self-evaluation: all signals stable or improving, no process changes needed.

Metrics

  • Total articles: 153
  • Coverage: 153 of 188 proposed concepts written (81%)
  • Articles edited since last deploy: 156 (2 new articles + 1 targeted edit + 1 sources audit + 152 via entry type markers sweep)

2026-04-05 (late)

What’s New

  • New article: Bounded Autonomy – how to calibrate agent freedom based on the consequence and reversibility of each action, from full autonomy for safe tasks to human-only for critical operations.
  • Improved: The Naming article received tighter prose, proper source attribution crediting Robert C. Martin and Phil Karlton, and a clearer presentation of naming principles.
  • Improved: The Refactor article now credits the people who originated the ideas it teaches – from Opdyke and Johnson coining the term in 1992, through Fowler’s canonical catalog, to Beck’s integration with testing.
  • Structural: Section index pages for Socio-Technical Systems and Agent Governance and Feedback now show a “Work in Progress” notice indicating more entries are on the way.
  • Other: Updated the Meta Report with the engine’s fifth self-evaluation: the draft-pressure fix is confirmed working, and the restructure action’s weight continues its planned decay.

Metrics

  • Total articles: 158
  • Coverage: 158 of 192 proposed concepts written (82%)
  • Articles edited since last deploy: 3 (1 targeted edit + 1 sources audit + 1 new article)

2026-04-06

What’s New

  • New article: Design Doc – how to translate requirements into a technical plan before building starts, and why this matters even more when an AI agent is the builder.
  • Improved: The Skill article gained a new section on how skills evolve from ad-hoc instructions into reliable team workflows, plus a new scenario showing code review skill evolution in practice.
  • Improved: The Ubiquitous Language article received proper source attribution, tighter prose in the agentic workflow section, and a new cross-link to the Instruction File pattern.
  • Improved: Added intellectual lineage to the Feedforward article, tracing the concept from 1920s control theory through Marshall Goldsmith’s coaching framework to Birgitta Boeckeler’s guides-and-sensors model.
  • Structural: Improved cross-reference navigation in the Security and Trust section – 14 missing reciprocal links added so readers can follow connections in both directions.
  • Other: Updated the Meta Report with the engine’s fourth self-evaluation: a procedural bug was keeping unreviewed articles from getting edited, now fixed with a clearer priority gate.

Metrics

  • Total articles: 158
  • Coverage: 158 of 189 proposed concepts written (84%)
  • Articles edited since last deploy: 10 (2 targeted edits + 1 sources audit + 1 groom pass across 6 articles)

2026-04-05 (evening)

What’s New

  • New article: Conway’s Law – why software systems end up mirroring the communication structure of the teams that build them, and how to use this force deliberately when organizing both human teams and AI agents. This is the first article in the new Socio-Technical Systems section.
  • Improved: Updated the Prompt Injection article with 2025-2026 developments: direct vs. indirect injection, MCP attack surfaces, instruction hierarchy defenses, multimodal vectors, and detection techniques like canary tokens.
  • Improved: Every pattern entry now shows prerequisite concepts at the top of the page – follow the links to drill down to foundational ideas before reading advanced ones.
  • Improved: The Test-Driven Development article now credits Kent Beck, the Extreme Programming community, Robert C. Martin, and Martin Fowler for the ideas it teaches.
  • Structural: Fixed paragraph line spacing to match the intended readability standard across all article pages.
  • Other: Updated the Meta Report with the engine’s second self-evaluation: the rotation rebalancing worked, all three hypotheses were resolved, and a course correction prevents the idea pipeline from drying up.

Metrics

  • Total articles: 149
  • Coverage: 149 of 169 proposed concepts written (88%)
  • Articles edited since last deploy: 107 (2 targeted edits + 1 sources audit + 104 via Understand This First sweep)

2026-04-05

What’s New

  • New article: Domain Model – how to capture the concepts, rules, and relationships of a business problem so that both humans and AI agents share the same understanding.
  • New article: Ubiquitous Language – how a shared vocabulary drawn from the business domain keeps developers, stakeholders, and AI agents aligned on what every term means.
  • New article: Naming – how choosing clear, consistent identifiers for code elements matters more in the agent era, where AI amplifies whatever naming patterns it finds.
  • New article: Bounded Context – how drawing explicit boundaries around parts of your system keeps domain models focused and prevents vocabulary collisions, especially when directing AI agents.
  • New article: Feedforward – how to steer an AI agent toward correct output before it acts, using instruction files, specifications, and computational checks.
  • New article: Feedback Sensor – how automated checks after each agent action detect mistakes and drive self-correction, from fast type checkers to LLM-based code reviewers.
  • New article: Steering Loop – how the closed cycle of act, sense, and adjust turns feedforward controls and feedback sensors into a system that converges on correct code.
  • New article: Harnessability – why some codebases are easier for AI agents to work in than others, and how type systems, module boundaries, and codified conventions determine the ceiling on agent effectiveness.
  • Improved: Added example prompts to 129 pattern entries, showing readers what it looks like to apply each concept when directing an AI coding agent.
  • Improved: The Harnessability article gained a practical optimization checklist – six concrete steps to make your codebase more tractable for AI agents.
  • Improved: The Domain Model article gained a new section on encoding behavior in domain objects, tighter prose, a corrected alias, and a Sources section crediting Eric Evans and Martin Fowler.
  • Improved: The Feedforward article received tighter prose and a corrected reference link.
  • Other: Published the first Meta Report entry, documenting how the improvement engine measures and adjusts its own process.

Metrics

  • Total articles: 155
  • Coverage: 155 of 178 proposed concepts written (87%)
  • Articles edited since last deploy: 132 (4 targeted edits + 1 sources audit + 129 via example-prompts sweep)

2026-04-04

What’s New

  • New article: Specification covers how to write what a system should do precisely enough for a human or an agent to build it correctly.
  • Improved: The Specification article received tighter prose, a unique epigraph, and new content on the three levels of spec-driven development.
  • Improved: Five core agentic coding articles (Context Window, Context Engineering, Prompt, Agent, Tool) now include example prompts showing how to apply each pattern when directing an AI agent.

Metrics

  • Total articles: 140
  • Coverage: 140 of 200 proposed concepts written (70%)
  • Articles edited since last deploy: 6