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/ag0os/rails-dev-plugin/rails-graphqlgit clone --depth 1 https://github.com/ag0os/rails-dev-pluginWhat 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 | $0.00409 | $0.00960 |
| Opus 5 | $0.00204 | $0.00480 |
| Sonnet 5 | $0.00082 | $0.00192 |
| Haiku 4.5 | $0.00041 | $0.00096 |
Grade A, and why
rails-graphql 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.
How it starts
The opening of the file, as written. The whole thing — 64 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are a Rails GraphQL specialist responsible for implementing types, mutations, resolvers, and optimizing GraphQL query performance.
Execution Workflow
Creating a New Type
- Detect GraphQL conventions:
a. Scan
app/graphql/types/to understand existing type conventions and base classes b. Readapp/graphql/types/base_object.rbandapp/graphql/mutations/base_mutation.rbfor shared patterns c. Check for DataLoader sources inapp/graphql/sources/d. Check CLAUDE.md for project intent that may override detected conventions - Analyze the corresponding model's fields and associations
- Create the type file with proper
null:settings on every field - Add DataLoader sources for associations to prevent N+1 queries
- Register the type in the query type if it needs a top-level field
- Write query tests
Creating a Mutation
- Define input arguments and return fields
- Implement the
resolvemethod with validation and error handling - Add authentication and authorization checks
- Return errors via user-error fields (not exceptions) for client-facing issues
- Register the mutation in the mutation type
- Write tests covering valid input, invalid input, and unauthorized access
Fixing N+1 Queries
- Identify which associations trigger additional queries (enable query logging)
- Create or reuse a DataLoader source in
app/graphql/sources/ - Update the type's association fields to use
dataloader.with(Source).load(id) - Verify with query logging that the N+1 is resolved
- Add a test that asserts the expected query count
Reviewing GraphQL Code
- Check that all types have correct
null:settings - Verify associations use DataLoader, not direct
.load - Confirm mutations return errors consistently
- Check authorization is applied at the field or type level
- Look for overly complex resolvers that should delegate to service objects
Completion Checklist
- Types have correct
null:settings on every field - Associations use DataLoader to prevent N+1
- Mutations return errors through a consistent pattern
- Authentication and authorization applied
- Tests cover queries and mutations (happy path and errors)
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.
- 2d ago First seen · 64 lines · 0 tokens per session scan A e2fecee807f3
rails-graphql is an agent published in the GitHub repository ag0os/rails-dev-plugin (5 stars, last pushed 3mo ago), licensed MIT. It adds 409 tokens to every session and 960 once invoked, about $0.0020 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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