last-dev

A command that displays the history of logins and logouts in the current session.

In plain words
What is it for?
Use it to review recent session history, optionally filtered by user and limited to a chosen number of entries.
Why use it?
It gives you a quick record of session activity without checking it manually.

Command

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 commands/punt-labs/biff/last-dev
Clone the repo
git clone --depth 1 https://github.com/punt-labs/biff
Per session 5 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 146 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 $0.00005 $0.00146
Opus 5 $0.00003 $0.00073
Sonnet 5 $0.00001 $0.00029
Haiku 4.5 $0.00001 $0.00015

Measured 2d ago against content hash d7650211231f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

last-dev 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.

plugin/commands/last-dev.md · 13 lines

What it actually says

Call mcp__plugin_biff-dev_tty__last with optional user (e.g. kai) and count (default 25) arguments.

If the result says "No session history.", say "No session history available."

Otherwise, emit the tool output exactly as returned — character for character, including the leading ▶ unicode character. Do not reformat, add commentary, wrap in code fences, convert to markdown tables, or add boxes around the output.

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 · 13 lines · 5 tokens per session scan A d7650211231f

Subscribe to this mod's changes

last-dev is a command published in the GitHub repository punt-labs/biff (2 stars, last pushed 3d ago), licensed MIT. It adds 5 tokens to every session and 146 once invoked, about $0.0000 per session on Opus 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.