hermes-plugin-backsearch

What hermes-plugin-backsearch does

BackSearch is a frozen news archive. Every request carries an as_of date, search returns only documents crawled on or before it, and fetch returns article text as archived at that time. The same query with the same as_of returns the same results every time, which suits forecasting backtests, quant research loops, RL environments and reproducible benchmarks where evidence after a cutoff must not leak in.

The plugin registers two model tools, backsearch and backfetch, which appear in the model schema only when OPENREWARD_API_KEY is set. backsearch runs hybrid search with optional k and allowed or blocked domains, and backfetch returns extracted page text with an optional prompt for a focused summary. The as_of date gates on crawl date rather than the publish date a page claims. The preview archive covers news domains from December 2025 to July 2026, and fetched text is capped at 15K characters. The plugin was extracted from hermes-agent pull request 71207 under the policy that third-party service integrations ship as plugins.

Key features

• backsearch tool: hybrid search over a frozen corpus as of a given date
• backfetch tool: page text from the latest capture on or before the cutoff
• Deterministic results: the same query and as_of give the same output
• as_of gates on crawl date, which prevents post-cutoff leakage
• Tools stay out of the model schema until OPENREWARD_API_KEY is set
• Optional prompt for a focused summary of long fetched pages

When to use it

• Backtesting forecasts without information from after the cutoff
• Building reproducible benchmarks and RL environments that use web evidence
• Running quant research loops that need date-bounded news search

Who it is for: Researchers and developers who need Hermes Agent to search the web as it looked on a past date.

How it fits with Hermes Agent

A plugin for Hermes Agent published in the NousResearch organization, extracted from the hermes-agent repository.

How to install hermes-plugin-backsearch

These commands are copied from the project's README. Check the repository for the latest steps before you run them.

git clone https://github.com/NousResearch/hermes-plugin-backsearch.git ~/.hermes/plugins/backsearch
hermes plugins enable backsearch
echo 'OPENREWARD_API_KEY=or_...' >> ~/.hermes/.env

Requirements: An OpenReward API key with a prepaid balance, set as OPENREWARD_API_KEY

Note: BackSearch bills per successful request against a prepaid OpenReward balance, and the current preview archive covers news domains from December 2025 to July 2026.

FAQ