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/blockchain-data-indexingWrote 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/blockchain-data-indexing)<a href="https://agentmods.dev/skills/j4flmao/agent-skills/blockchain-data-indexing"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-data-indexing/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/blockchain-data-indexing"><img src="https://agentmods.dev/badge/skills/j4flmao/agent-skills/blockchain-data-indexing.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 | $0.00093 | $0.05123 |
| Opus 5 | $0.00046 | $0.02561 |
| Sonnet 5 | $0.00019 | $0.01025 |
| Haiku 4.5 | $0.00009 | $0.00512 |
Grade A, and why
blockchain-data-indexing 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 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.
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 — 547 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Blockchain Data Indexing
Purpose
Guide the selection and implementation of blockchain data indexing solutions. Covers The Graph subgraphs, Dune Analytics queries, Goldsky pipelines, and custom indexer architecture for transforming raw on-chain data into queryable formats.
Agent Protocol
Trigger Keywords
"blockchain indexer", "subgraph", "The Graph", "Dune Analytics", "Dune", "Goldsky", "ChainIndex", "indexer architecture", "event indexing", "event handler", "call handler", "block handler", "data source template", "dynamic data source", "spellbook", "decoded table", "pipeline", "mirror", "ETL blockchain", "reorg handling", "chain reorg", "log polling", "event-driven indexing", "fromBlock", "toBlock", "healing"
Input Context
- Blockchain and chain(s) to index
- Data to extract (events, calls, state, traces)
- Query patterns (analytical, real-time, historical)
- Infrastructure preferences (managed service vs self-hosted)
- Budget constraints (gas costs, infrastructure costs)
- Reorg tolerance (confirmation depth)
Output Artifact
Indexing architecture recommendation with configuration, schema design, and production operational plan.
Response Format
- Recommendation: tool/protocol fitting the use case (The Graph, Dune, Goldsky, ChainIndex, hybrid)
- Architecture: indexing pipeline (source chain → data source → transformation → storage → query layer)
- Configuration snippet: YAML/SQL/AssemblyScript excerpt (subgraph.yaml, Dune query, Goldsky pipeline, event handler)
- Reorg & safety: how design handles reorgs, missing blocks, data consistency
- Alternatives/trade-offs: when another approach is better and why
Completion Criteria
- Indexing tool selected with justification against alternatives
- Event schema designed with all indexed fields for efficient filtering
- Reorg handling modeled with confirmation depth and unwind logic
- Query patterns optimized (time-range filters, pagination, aggregations)
- Monitoring metrics defined (indexing lag, reorgs, error rate)
What ships with it
10 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/blockchain-data-indexing-advanced.md 1.8 KB
- references/blockchain-data-indexing-fundamentals.md 1.8 KB
- references/blockchain-data-query.md 7.8 KB
- references/dune-analytics.md 6.0 KB
- references/event-processing.md 2.1 KB
- references/goldsky-chainindex.md 5.4 KB
- references/indexer-architecture.md 7.3 KB
- references/subgraph_mapping_handlers.md 454 KB
- references/the_graph_graphql_schemas.md 454 KB
- references/the-graph-subgraph.md 7.0 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 · 547 lines · 93 tokens per session scan A 169311b4f45e
blockchain-data-indexing is a skill published in the GitHub repository j4flmao/agent-skills (23 stars, last pushed 5d ago), licensed MIT. It adds 93 tokens to every session and 5,123 once invoked, about $0.0005 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 2026-09-03.
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