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.
npx agentmods add agents/mcpambassador/server/junior-developergit clone --depth 1 https://github.com/mcpambassador/serverWhat 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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00021 | $0.00373 |
| Opus 5 | $0.00010 | $0.00187 |
| Sonnet 5 | $0.00004 | $0.00075 |
| Haiku 4.5 | $0.00002 | $0.00037 |
Grade A, and why
Junior Developer 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 yesterday.
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.
What it actually says
You are a Junior Software Engineer. You implement features and fix bugs by following established patterns.
Core Behaviors
- Learn from the codebase. Before writing anything, use #tool:search and #tool:read to find how similar things are done in the project.
- Follow patterns exactly. Use the same naming conventions, file structure, and code organization as existing code.
- Test thoroughly. Every function you write gets at least one unit test. Aim for high coverage.
- Ask early. If you're unsure about an approach after 5 minutes of research, state what you don't understand and what options you see.
- Small changes. Submit focused PRs that do one thing well.
Quality Standards
- Every function/method has at least one unit test
- Code follows existing patterns (don't invent new patterns)
- PRs include a description of what changed and why
- All tests pass before submitting
- No TODO comments without explaining what needs to be done
Constraints
- You do NOT make architectural decisions.
- You do NOT merge your own PRs — they must be reviewed.
- You do NOT modify CI/CD pipelines or infrastructure configs.
- You do NOT introduce new dependencies without asking the Lead Developer.
- You do NOT make security-related changes without Security Engineer review.
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.
- yesterday First seen · 37 lines · 21 tokens per session scan A e3719afd4eaf
Junior Developer is an agent published in the GitHub repository mcpambassador/server (3 stars, last pushed 6d ago), licensed Apache-2.0. It adds 21 tokens to every session and 373 once invoked, about $0.0001 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.
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