blast-radius

A dependency checker for a class, function, or method. It lists files and code elements that import, call, extend, inject, or render the named symbol.

In plain words
What is it for?
Run it before modifying a symbol to identify affected code and plan a staged change when many dependencies are found.
Why use it?
It shows the likely impact of changing, moving, renaming, or deleting code before you make the change. This helps reveal callers and consumers that ordinary text search may miss.

Command for Claude Code

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 commands/cognitx-leyton/codegraph/blast-radius
Clone the repo
git clone --depth 1 https://github.com/cognitx-leyton/codegraph

Made for: Claude Code.

Per session 24 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 839 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 $0.00024 $0.00839
Opus 5 $0.00012 $0.00419
Sonnet 5 $0.00005 $0.00168
Haiku 4.5 $0.00002 $0.00084

Measured 2d ago against content hash 6a8e085fe38f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

blast-radius 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.

.claude/commands/blast-radius.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Usage

/blast-radius <SymbolName>

Returns every site that would break (or need updating) if you changed the named symbol. Unions five edge kinds in a single query:

Edge Captures
IMPORTS_SYMBOL Files that explicitly import the symbol by name
CALLS Methods that call a method of that name (typed or name-based resolution)
EXTENDS Subclasses that'd break if the base changes
INJECTS NestJS DI consumers
RENDERS React components that render the symbol

Run it before any rename / move / delete. If nothing comes back, the symbol is safe to touch. If many callers come back, you're probably looking at a staged migration.

What this does

codegraph query "
MATCH (caller:File)-[r:IMPORTS_SYMBOL]->(source:File)
WHERE r.symbol = '$ARGUMENTS'
RETURN 'IMPORTS_SYMBOL' AS edge, caller.path AS caller, '' AS caller_sym, source.path AS defined_in, r.symbol AS symbol
UNION ALL
MATCH (caller:Method)-[c:CALLS]->(target:Method)
WHERE target.name = '$ARGUMENTS'
RETURN 'CALLS' AS edge, caller.file AS caller, caller.name AS caller_sym, target.file AS defined_in, target.name AS symbol
UNION ALL
MATCH (sub:Class)-[:EXTENDS]->(parent:Class)
WHERE parent.name = '$ARGUMENTS'
RETURN 'EXTENDS' AS edge, sub.file AS caller, sub.name AS caller_sym, parent.file AS defined_in, parent.name AS symbol
UNION ALL
MATCH (consumer:Class)-[:INJECTS]->(injected:Class)
WHERE injected.name = '$ARGUMENTS'
RETURN 'INJECTS' AS edge, consumer.file AS caller, consumer.name AS caller_sym, injected.file AS defined_in, injected.name AS symbol
UNION ALL
MATCH (parent:Function)-[:RENDERS]->(child:Function)
WHERE child.name = '$ARGUMENTS'
RETURN 'RENDERS' AS edge, parent.file AS caller, parent.name AS caller_sym, child.file AS defined_in, child.name AS symbol
LIMIT 200
"

The --json flag is optional; add it for machine-parseable output. The default-rendered Rich table is easier to eyeball.

Caveats

  • Name collisions are a feature. If two classes share a name in different packages, both show up. That's usually what you want when assessing blast radius.
  • Python CALLS is method-only. The resolver wires Python CALLS edges from method bodies; module-level function → method calls aren't tracked (Stage 1 limitation). Callers that live in a top-level function may be missed.
  • Aliased re-exports. If pkg/__init__.py re-exports Foo and another file does from pkg import Foo, the IMPORTS_SYMBOL edge points at the re-export, not the original definition — you'll see both in the blast-radius output.
  • 200-row limit. Raise the LIMIT 200 at the bottom of the query if you hit it on a very-central symbol.

Read the full file on GitHub · 67 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. 2d ago First seen · 67 lines · 24 tokens per session scan A 6a8e085fe38f

Subscribe to this mod's changes

blast-radius is a command published in the GitHub repository cognitx-leyton/codegraph (11 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 24 tokens to every session and 839 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 2026-08-30.