Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/j4flmao/agent-skillsnpx agentmods add skills/j4flmao/agent-skills/graphql-federationWrote 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.
[](https://agentmods.dev/skills/j4flmao/agent-skills/graphql-federation)<a href="https://agentmods.dev/skills/j4flmao/agent-skills/graphql-federation"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/graphql-federation/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.
<a href="https://agentmods.dev/skills/j4flmao/agent-skills/graphql-federation"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/graphql-federation.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00071 | $0.06093 |
| Opus 5 | $0.00036 | $0.03047 |
| Sonnet 5 | $0.00014 | $0.01219 |
| Haiku 4.5 | $0.00007 | $0.00609 |
Grade A, and why
api-graphql-federation scanned grade A with 1 finding 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 8d 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -f http://localhost:4001/.well-known/apollo/server-health How it starts
The opening of the file, as written. The whole thing — 763 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GraphQL Federation
Purpose
Design and implement GraphQL Federation: compose multiple subgraphs into a unified supergraph, manage distributed GraphQL architecture, and scale GraphQL across teams. Make informed build-vs-buy decisions between Apollo Federation and alternative distributed graph strategies.
Workflow
Federation Architecture
Supergraph (Apollo Router / Gateway)
├── Subgraph A (Users service) — @key(fields: "id")
├── Subgraph B (Orders service) — @key(fields: "id") @extends User
├── Subgraph C (Reviews service) — @key(fields: "id") @extends User
└── Subgraph D (Inventory service) — standalone
Apollo Federation vs. GraphQL Mesh Decision Tree
Use this decision framework when choosing between Apollo Federation and GraphQL Mesh:
| Criterion | Apollo Federation | GraphQL Mesh |
|---|---|---|
| Schema ownership | Each subgraph owns its schema | Sources are existing APIs (REST, gRPC, SOAP, etc.) |
| Team topology | Multiple teams own separate subgraphs | Single team integrating existing backends |
| Source types | Native GraphQL only | Any source (REST, OpenAPI, gRPC, SQL, SOAP, etc.) |
| Composition model | Static composition via Rover CLI | Runtime schema stitching |
| Gateway | Apollo Router (Rust) or Gateway (Node.js) | Envelop, Yoga, or custom |
| Federation directives | @key, @extends, @requires, @provides, @shareable | Transformers, handlers, mesh config |
| Entity resolution | Built-in via __resolveReference | Manual stitching resolvers |
| Query planning | Automatic query planner | Manual or custom merge config |
| Performance | Optimized Rust router, plan caching | Depends on underlying gateway |
| Ecosystem maturity | Mature (Apollo GraphOS, Studio) | Growing (The Guild ecosystem) |
| When to choose | Greenfield GraphQL with multiple teams | Wrapping legacy/heterogeneous backends |
Decision flow:
- Are all your sources already GraphQL? → Apollo Federation
- Do you need to wrap REST/gRPC/SQL backends? → GraphQL Mesh
- Do you have 3+ teams owning separate domains? → Apollo Federation
- Is your primary goal API unification of legacy systems? → GraphQL Mesh
- Hybrid approach: Use Mesh to convert REST → GraphQL, then compose those as subgraphs via Federation
What ships with it
14 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/entity-resolution.md 11 KB
- references/federated-tracing.md 7.9 KB
- references/federation-architecture.md 6.9 KB
- references/federation-cost-management.md 12 KB
- references/federation-deployment.md 2.9 KB
- references/federation-migration-monolith.md 11 KB
- references/federation-performance.md 8.7 KB
- references/federation-security.md 10 KB
- references/federation-testing.md 3.0 KB
- references/federation-vs-mesh.md 5.1 KB
- references/graphql-federation-advanced.md 16 KB
- references/graphql-federation-fundamentals.md 14 KB
- references/supergraph-composition.md 8.8 KB
- references/supergraph-config.md 8.1 KB
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.
- 8d ago First seen · 763 lines · 71 tokens per session scan A 211030f51a97
api-graphql-federation is a skill published in the GitHub repository j4flmao/agent-skills (23 stars, last pushed 5d ago), licensed MIT. It adds 71 tokens to every session and 6,093 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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