run-eval

A regression-checking tool for AI agents that compares new results with saved expected results, called golden baselines.

In plain words
What is it for?
Use it after changing an AI agent to run test cases and identify passed checks, changed outputs or tools, and regressions.
Why use it?
It shows whether code, prompt, model, or tool changes altered agent behavior or caused a meaningful drop in quality.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/hidai25/eval-view/run-eval
Any agent
npx skills add hidai25/eval-view --skill run-eval
Clone the repo
git clone --depth 1 https://github.com/hidai25/eval-view

Made for: Claude Code, Codex.

Per session 30 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 503 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00030 $0.00503
Opus 5 $0.00015 $0.00251
Sonnet 5 $0.00006 $0.00101
Haiku 4.5 $0.00003 $0.00050

Measured 3d ago against content hash 5f5b1ac50c34, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

run-eval scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/run-eval/SKILL.md · 49 lines

How it starts

The opening of the file, as written. The whole thing — 49 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Run Eval

Use this skill after making changes to an AI agent (prompt edits, model swaps, tool changes, code refactors) to verify nothing broke.

What this does

EvalView compares current agent behavior against saved golden baselines. It runs your test cases, evaluates the outputs, and reports a diff status for each test:

  • PASSED — behavior matches the baseline
  • OUTPUT_CHANGED — output shifted but may be intentional
  • TOOLS_CHANGED — different tools were called
  • REGRESSION — score dropped significantly (blocking failure)

Steps

  1. Locate the test directory. Look for tests/evalview/ in the project. If it exists, use that. Otherwise check for a tests/ directory with .yaml test files.

  2. Run a regression check using the run_check MCP tool:

    • If checking all tests: call run_check with the detected test_path
    • If checking a specific test: also pass the test parameter with the test name
  3. Interpret results:

    • If all tests pass, confirm to the user that no regressions were found
    • If REGRESSION is reported, show the diff (score delta, tool changes, output similarity) and offer to help fix it
    • If OUTPUT_CHANGED or TOOLS_CHANGED, flag it as a warning — the user should decide if the change is intentional
  4. If changes are intentional, offer to update the baseline by calling run_snapshot with an explanatory notes parameter.

  5. Generate a visual report (optional) by calling generate_visual_report for a detailed HTML breakdown of traces, diffs, scores, and timelines.

CLI equivalent

evalview check tests/evalview/
evalview check tests/evalview/ --test "my-test"
evalview snapshot tests/evalview/ --notes "updated after prompt refactor"

Tips

  • Use run_check frequently — it calls the Python API directly with no subprocess overhead.
  • A score delta near zero with TOOLS_CHANGED often means the agent found an equivalent path.
  • Always snapshot after confirming intentional changes so future checks compare against the new baseline.

Read the full file on GitHub · 49 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 49 lines · 30 tokens per session scan A 5f5b1ac50c34

Subscribe to this mod's changes

run-eval is a skill published in the GitHub repository hidai25/eval-view (133 stars, last pushed 10d ago), licensed Apache-2.0. It adds 30 tokens to every session and 503 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.