bifrost-code-mode

bifrost-code-mode is a skill for Claude Code, Codex from neXenio/bifrost-plugin. It costs 112 tokens per session (1,423 once invoked), scanned A, original, MIT.

A way to use tools on a Bifrost gateway when they are not listed as separate callable tools. It discovers their definitions and runs them through a code-based interface using short Starlark snippets.

In plain words
What is it for?
Use it to list available tool files, read their definitions, check exact signatures, and execute tools that are exposed through Bifrost code mode.
Why use it?
It helps avoid treating an available capability as missing and reduces errors caused by using the wrong tool name or parameters.

Skill for Claude CodeCodex

Part of the bifrost-plugin plugin — 5 skills, 5 commands, 5 hooks, 1 MCP server shipped together

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 skills/nexenio/bifrost-plugin/bifrost-code-mode
Any agent
npx skills add neXenio/bifrost-plugin --skill bifrost-code-mode
Clone the repo
git clone --depth 1 https://github.com/neXenio/bifrost-plugin

Made for: Claude Code, Codex.

Or install bifrost-plugin, the plugin that ships this one along with the rest of its 5 skills, 5 commands, 5 hooks, 1 MCP server.

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 bifrost-code-mode

README.md
[![agentmods](https://agentmods.dev/badge/skills/nexenio/bifrost-plugin/bifrost-code-mode.svg)](https://agentmods.dev/skills/nexenio/bifrost-plugin/bifrost-code-mode)
Your own site
<a href="https://agentmods.dev/skills/nexenio/bifrost-plugin/bifrost-code-mode"><img src="https://agentmods.dev/badge/skills/nexenio/bifrost-plugin/bifrost-code-mode.svg" alt="Measured on agentmods" height="20"></a>
Per session 112 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,423 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 $0.00112 $0.01423
Opus 5 $0.00056 $0.00711
Sonnet 5 $0.00022 $0.00285
Haiku 4.5 $0.00011 $0.00142

Measured 3d ago against content hash 1e4f9e20b46e, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

bifrost-code-mode 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.

skills/bifrost-code-mode/SKILL.md · 152 lines

How it starts

The opening of the file, as written. The whole thing — 152 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Bifrost code mode

Most servers on a Bifrost gateway are not flat tools. They do not appear in your tool list and mcp__bifrost__<server>-<tool> does not exist for them. They are reached by writing a short Starlark snippet and running it with executeToolCode.

If a capability seems missing, it is almost certainly here. Do not conclude the gateway lacks it, and do not fall back to guessing from training data, until you have checked.

The four meta-tools

Exact schemas, as the gateway advertises them:

Tool Parameters Required
listToolFiles (none)
readToolFile fileName, startLine, endLine fileName
getToolDocs server, tool both
executeToolCode code code

The parameter is fileName, not path or file. Passing path fails with fileName parameter is required and must be a string.

fileName is the full catalog path: servers/<server>/<tool>.pyi.

Workflow

1. Discover. listToolFiles() returns the catalog, grouped by server:

servers/
  jira/
    search_jira_tickets.pyi
    create_jira_ticket.pyi
    ...

2. Confirm the signature. Never call a tool whose parameters you have not read.

readToolFile(fileName="servers/jira/search_jira_tickets.pyi")

returns a typed stub with the exact callable name and an inline description:

# Total lines: 10 (this is the complete file, no need to paginate)
# jira.search_jira_tickets tool
# Usage: jira.tool_name(param=value)
def search_jira_tickets(query: str, max_results: float = None, service: str = None, status: str = None) -> dict:  # Search JIRA before filing a new ticket to avoid duplicates.

The def name is the exact callable. Descriptions in .pyi files may be truncated — use getToolDocs(server="jira", tool="search_jira_tickets") when a parameter's meaning or return shape is unclear.

A wrong tool name is cheap to recover from: the error lists every valid tool on that server.

3. Execute.

Read the full file on GitHub · 152 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. 3d ago First seen · 152 lines · 112 tokens per session scan A 1e4f9e20b46e

Subscribe to this mod's changes

bifrost-code-mode is a skill published in the GitHub repository neXenio/bifrost-plugin (2 stars, last pushed 15d ago), licensed MIT. It adds 112 tokens to every session and 1,423 once invoked, about $0.0006 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.