Anthropic's current lineup is Claude Haiku 4.5, Claude Sonnet 5 (released June 30, 2026), Claude Opus 5 (released July 24, 2026), and Claude Fable 5, with Claude Mythos 5 restricted to approved partners. Sonnet 5 is the default model on the Free and Pro plans, Opus 5 is the default on Max and the strongest model available on Pro. Source: Anthropic.
The test runs on this page were performed on Claude Sonnet 4.6, which Sonnet 5 replaced as the default model on June 30, 2026. We publish these results as a dated snapshot rather than restating them as current-model behavior. Where a finding has not been re-tested on Sonnet 5 or Opus 5, treat it as history, not as a live bug report.
Most Claude guides explain the basics. We find the edge cases, document the failures, and publish what actually happens when you push the model to its limits. That is the only way to know if a technique actually works.
Who We Are
ClaudeAIGuide.com is an independent research publication run by the Cole Bridges Research Lab, a team of AI logic auditors who work with Claude on live production environments daily. We are not affiliated with Anthropic PBC. We are researchers who test every claim before it goes on this site.
Every technique, benchmark, and framework published here is stress-tested on a live Claude model before publication. If we cannot reproduce a result, we do not publish it. Each verified page carries a seal naming the exact model it was tested on and the month it was checked, so you always know how old a result is. Anthropic shipped Sonnet 5 on June 30, 2026 and Opus 5 on July 24, 2026, and our re-test queue is worked in traffic order.
What Makes This Site Different
Anthropic already explains what Claude can do. Thousands of blogs copy that explanation. We do not compete with that. Our focus is the opposite: what Claude gets wrong, where it breaks, and how to engineer around those failures.
Every page on this site is built around one question: what can go wrong, and what is the fix? That pivot from tutorial to stress-testing source is what separates technical credibility from generic AI content.
Our Research Focus Areas
- Instruction Drift, documenting when and why Claude ignores early prompt instructions in long sessions
- XML-Anchoring, testing which tag placements re-focus model attention most reliably across Sonnet-class models
- Silent Failure Detection, identifying confident but mathematically wrong outputs before they reach clients
- Context Window Stress, measuring where reasoning quality degrades across the 1M token context window
- Safety Refusal Accuracy, tracking false positive refusal rates on legitimate technical queries
The Cole Bridges Research Lab Network
ClaudeAIGuide.com is part of the Cole Bridges Research Lab brand, which also operates PromptSmarterAI.com, a live prompt engineering toolkit where the frameworks documented here are built and tested. Think of ClaudeAIGuide as the deep-dive technical documentation, and PromptSmarterAI as the hands-on implementation tool.
No AI-generated placeholders. Every guide is written, tested, and reviewed by a human researcher on the Cole Bridges team. Model verification: results are stamped with the model and month tested. Current published set was run on Sonnet 4.6, May 2026, and is being re-run against Sonnet 5.
Trust Signals
- Model Verification: every guide names the model and month it was tested; re-tests follow each new Anthropic default
- Logic audited for System-Prompt Integrity and Instruction Hierarchy compliance
- Cross-referenced against PromptSmarterAI Labs framework library
- No AI-slop content, every claim is reproducible
Found an Error?
AI moves fast. If you find a technique that no longer works as documented, or a result that differs from what we published, we want to know. Report an error here, we review every submission and update the relevant page within 72 hours.
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