echo

A test agent named echo that accepts text and returns the same text as a result.

In plain words
What is it for?
Testing configuration, prompts, inputs, outputs, and connections in a multi-agent setup.
Why use it?
It provides a simple way to check an agent pipeline, the sequence that passes data between agents, without complex processing.

Agent

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 agents/romainlentz/singleton_pipeline/echo
Clone the repo
git clone --depth 1 https://github.com/RomainLENTZ/singleton_pipeline
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 66 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 $0.00000 $0.00066
Opus 5 $0.00000 $0.00033
Sonnet 5 $0.00000 $0.00013
Haiku 4.5 $0.00000 $0.00007

Measured 2d ago against content hash 7844d33429e9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

echo 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 2d 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.

packages/cli/src/__fixtures__/agents/echo.md · 17 lines

What it actually says

Echo

Config

  • id: echo
  • description: Test fixture agent
  • inputs: text
  • outputs: result
  • provider: claude
  • model: claude-haiku-4-5

Prompt

Echo the input.

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. 2d ago First seen · 17 lines · 0 tokens per session scan A 7844d33429e9

Subscribe to this mod's changes

echo is an agent published in the GitHub repository RomainLENTZ/singleton_pipeline (5 stars, last pushed 2mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 66 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 2026-08-31.