hippo

hippo is a skill for Claude Code from Dev-Jahn/hippocampus. It costs 13 tokens per session (1,095 once invoked), scanned A, original, MIT.

A memory and task record for a coding agent. It stores delegated work, decisions, outcomes, and the instructions that are still active.

In plain words
What is it for?
Use it to add and complete tasks, record delegations and results, and view active instructions or recent records.
Why use it?
It reduces the chance of losing context between tasks or forgetting what was accepted, rejected, or still pending.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions subagents; mentions Claude Code; runs codex exec.

Part of the hippo plugin — 3 skills, 1 agent, 2 hooks shipped together

Good fit Use it to add and complete tasks, record delegations and results, and view active instructions or recent records.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/dev-jahn/hippocampus/hippo
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.

Any agent
npx skills add Dev-Jahn/hippocampus --skill hippo
Clone the repo
git clone --depth 1 https://github.com/Dev-Jahn/hippocampus

Made for: Claude Code.

Or install hippo, the plugin that ships this one along with the rest of its 3 skills, 1 agent, 2 hooks.

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 hippo

README.md
[![agentmods](https://agentmods.dev/badge/skills/dev-jahn/hippocampus/hippo/github.svg)](https://agentmods.dev/skills/dev-jahn/hippocampus/hippo)
Your own site
<a href="https://agentmods.dev/skills/dev-jahn/hippocampus/hippo"><img src="https://agentmods.dev/badge/skills/dev-jahn/hippocampus/hippo/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for hippo

Your own site · 80×15
<a href="https://agentmods.dev/skills/dev-jahn/hippocampus/hippo"><img src="https://agentmods.dev/badge/skills/dev-jahn/hippocampus/hippo.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 13 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,095 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 $0.00013 $0.01095
Opus 5.5 $0.00005 $0.00438
Sonnet 5.5 $0.00003 $0.00219
Haiku 4.5 $0.00001 $0.00110

Measured 5d ago against content hash 43b746b49d43, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

hippo 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 5d 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/hippo/SKILL.md · 75 lines

How it starts

The opening of the file, as written. The whole thing — 75 lines — stays where its author put it; the contents beside it link to each section on GitHub.

hippo — the project's hippocampus

hippo does not control you; it holds the memory — what you delegated, what was accepted or refuted, which of the user's instructions are still alive. The judgment is always yours.

Grammar

hippo init
hippo status [--inject]
hippo task add <type>/<slug> --title T [--notes N] [--deps a,b]
    [--status pending|active|done|dropped]
hippo task set <id> title|status|notes|deps <value>      # positional: no --flags
hippo task done <id> [--note N]
hippo task list [--status s1,s2] [--all] [--json]
hippo task show <id> [--json]
hippo task drop <id>
hippo log dispatch --id D --kind K --exec executor/model/effort --scope S
    [--task T] [--depth N] [--parent D]
hippo log outcome --ref <dispatch-id>|task:<task-id> --result accepted|revised|refuted|no-go|lost
    [--attr work|brief|harness] [--rework N] [--by executor/model] [--note N]
hippo log outcome --from-batch <journal> [--dry-run] < verdicts.jsonl
hippo log review --id R --base <sha> --source S --findings N
hippo log review-status --ref R --addressed full|partial|none [--at <sha>]
hippo log raw '<json>'
hippo log tail [-n N] [--ev TYPE]
hippo directive add --text T [--id kebab-id] [--audience main|executor|all]
    [--state active|withdrawn|expired]
hippo directive list [--active] [--json]
hippo directive withdraw <id>
hippo prior show
hippo prior distill [--days N]
hippo dispatch --kind K --scope S [--task T] [--depth N] [--fast] [--] <codex exec args…>
hippo dispatch --batch <manifest.yaml> [--dry-run | --entry <id>]  # --entry: the Workflow face's call, never typed
hippo dispatch --watch <dispatch-id|batch-id> [--for SECONDS]
# a bare noun reads: task → list, log → tail, directive → list, prior → show

When

  • Work will outlive this turn → task add; task done when it ships.
  • A delegation gets a verdict → log outcome (--ref task:<id> finds its open dispatch).
  • The user rules → directive add; re-add the same --id to change it, withdraw when done, --audience main when a lane never needs it. A rule for the next answer only is not one.
  • An external review arrives → log review; its findings dealt with → log review-status.
  • Before routing a delegation → prior.
  • Codex lanes → dispatch (--batch for many, --watch <id> to wait); see /hippo:dispatch.
  • A subagent or Workflow run (Codex: a spawn_agent child): no call; the scribe records it and your verdict, in Claude Code as ag-<agentId> or, once a Workflow ends, ag-wf_… (Run ID, not Task ID): name it in its verdict. One task id in its brief links it.
  • Lost your place → status.

Read the full file on GitHub · 75 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. 5d ago Changed 43b746b49d43
  2. 21d ago Changed a4c15eff098c
  3. 22d ago Changed · +1 lines 5ca20f813141
  4. 23d ago Changed · +8 lines 52fce3606395
  5. 24d ago Changed · +5 lines ed5c2204ae67
  6. 1mo ago First seen · 61 lines · 13 tokens per session scan A ee57ac2b1c9e

Subscribe to this mod's changes

hippo is a skill published in the GitHub repository Dev-Jahn/hippocampus (4 stars, last pushed 5d ago), licensed MIT. It adds 13 tokens to every session and 1,095 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-31.

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