How do I install the Xfilter skill?

Run npx skillmds@latest add vimalinx/xfilter in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

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Which AI agents work with Xfilter?

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Is Xfilter free to use?

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Who published Xfilter?

vimalinx (@vimalinx) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Xfilter by vimalinx — Agent Skill

Name: Xfilter
Rating: 4.5 (4 reviews)
Author: vimalinx

File contents

xfilter

Local-postings filter built on xcommon.sh, word-at-a-time, and rchive -query. It consumes UIDs from stdin or command-line sources, applies a query expression against a local postings index, and emits either raw filtered UIDs or an ENTREZ_DIRECT wrapper message.

Quick Start

Command: xfilter -query "<expression>"
Local executable: /home/vimalinx/miniforge3/envs/bio/bin/xfilter
Critical environment: EDIRECT_LOCAL_ARCHIVE

When To Use This Tool

Filtering UIDs against a local postings index instead of using remote efilter
Narrowing a local UID set with a query expression after xfetch/xsearch-style workflows
Producing either raw UID output (-raw) or an ENTREZ_DIRECT XML wrapper for downstream local tools
Working inside a fully local PubMed/PMC archive setup

Common Patterns

# Filter a UID stream with a local query
printf '2539356\n' | xfilter -db pubmed -query 'dna repair'

# Emit raw UIDs instead of ENTREZ_DIRECT XML
printf '2539356\n' | xfilter -db pubmed -raw -query 'dna repair'

# Show usage
xfilter -h

Recommended Workflow

Ensure the local postings environment is configured through EDIRECT_LOCAL_ARCHIVE.
Supply UIDs by -id, -input, stdin, or an upstream ENTREZ_DIRECT message.
Use -query with the local postings syntax you intend to test.
Add -raw only when a downstream stage expects plain UID lines instead of wrapper XML.

Guardrails

This is a local-postings query tool, not a remote Entrez filter.
-h/--help are safe and show usage examples; --version is not supported and locally triggered the missing-path error plus ERROR: Unrecognized option --version.
Source inspection shows xfilter always calls FindPostingsFolder before querying, so a valid local postings directory is mandatory.
In live testing without local postings configured, printf '2539356\n' | xfilter -db pubmed -query 'dna repair' failed with Unable to get folder Postings for database pubmed.
Query handling prepends [PIPE] AND in the common case, and UID input is tokenized through word-at-a-time before being sent to rchive -query.

---name: xfilterdescription: Use when filtering a UID stream against a local postings index with a query expression in the `x*` local-archive toolchain.---# xfilterLocal-postings filter built on `xcommon.sh`, `word-at-a-time`, and `rchive -query`. It consumes UIDs from stdin or command-line sources, applies a query expression against a local postings index, and emits either raw filtered UIDs or an `ENTREZ_DIRECT` wrapper message.## Quick Start- **Command:** `xfilter -query "<expression>"`- **Local executable:** `/home/vimalinx/miniforge3/envs/bio/bin/xfilter`- **Critical environment:** `EDIRECT_LOCAL_ARCHIVE`## When To Use This Tool- Filtering UIDs against a local postings index instead of using remote `efilter`- Narrowing a local UID set with a query expression after `xfetch`/`xsearch`-style workflows- Producing either raw UID output (`-raw`) or an `ENTREZ_DIRECT` XML wrapper for downstream local tools- Working inside a fully local PubMed/PMC archive setup## Common Patterns```bash# Filter a UID stream with a local queryprintf '2539356\n' | xfilter -db pubmed -query 'dna repair'``````bash# Emit raw UIDs instead of ENTREZ_DIRECT XMLprintf '2539356\n' | xfilter -db pubmed -raw -query 'dna repair'``````bash# Show usagexfilter -h```## Recommended Workflow1. Ensure the local postings environment is configured through `EDIRECT_LOCAL_ARCHIVE`.2. Supply UIDs by `-id`, `-input`, stdin, or an upstream `ENTREZ_DIRECT` message.3. Use `-query` with the local postings syntax you intend to test.4. Add `-raw` only when a downstream stage expects plain UID lines instead of wrapper XML.## Guardrails- This is a local-postings query tool, not a remote Entrez filter.- `-h`/`--help` are safe and show usage examples; `--version` is not supported and locally triggered the missing-path error plus `ERROR: Unrecognized option --version`.- Source inspection shows `xfilter` always calls `FindPostingsFolder` before querying, so a valid local postings directory is mandatory.- In live testing without local postings configured, `printf '2539356\n' | xfilter -db pubmed -query 'dna repair'` failed with `Unable to get folder Postings for database pubmed`.- Query handling prepends `[PIPE] AND` in the common case, and UID input is tokenized through `word-at-a-time` before being sent to `rchive -query`.

Frequently asked questions

Xfilter