json.exists

json.exists is a command for Claude Code from stratalab/strata-core. It costs 0 tokens per session (46 once invoked), scanned A, original, Apache-2.0.

A database command that checks whether one JSON document exists without loading its contents.

In plain words
What is it for?
Use it to test whether a document key is available before reading, creating, updating, or deleting a record.
Why use it?
It avoids transferring and processing document data when only existence matters.

Command for Claude Code

Written for Claude Code: a Claude Code command (commands/*.md).

Good fit Use it to test whether a document key is available before reading, creating, updating, or deleting a record.

Compare 6 commands from other repositories ↓
Install with agentmods
npx agentmods add commands/stratalab/strata-core/json.exists
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.

Clone the repo
git clone --depth 1 https://github.com/stratalab/strata-core

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for json.exists

README.md
[![agentmods](https://agentmods.dev/badge/commands/stratalab/strata-core/json.exists.svg)](https://agentmods.dev/commands/stratalab/strata-core/json.exists)
Your own site
<a href="https://agentmods.dev/commands/stratalab/strata-core/json.exists"><img src="https://agentmods.dev/badge/commands/stratalab/strata-core/json.exists.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 46 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00000 $0.00046
Opus 5 $0.00000 $0.00023
Sonnet 5 $0.00000 $0.00009
Haiku 4.5 $0.00000 $0.00005

Measured 3d ago against content hash 2cf54b2d02cc, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

json.exists 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.

crates/executor/idl/v1/prose/commands/json.exists.md · 7 lines

What it actually says

Returns a boolean status for one JSON document key without loading the stored document.

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 · 7 lines · 0 tokens per session scan A 2cf54b2d02cc

Subscribe to this mod's changes

json.exists is a command published in the GitHub repository stratalab/strata-core (2 stars, last pushed today), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 46 tokens. 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 2026-09-03.