mastodon_media_prune
Manually trigger pruning of cached remote media older than N days. The sidekiq scheduler handles this on a recurring cadence (MEDIA_CACHE_RETENTION_PERIOD env); this lets operators force an aggressive pass. Rate-limited: 2/hour.
This record as markdown: /tools/kh0pper-crow/mastodon-media-prune.md
What mastodon_media_prune does on Crow
AI agents call mastodon_media_prune to permanently remove resources in Crow, typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
Why mastodon_media_prune is rated Critical
Pruning cached media files is an irreversible deletion operation — once remote cached media is purged, it cannot be recovered without re-fetching from the original source (which may no longer be available). The 'force an aggressive pass' language confirms it can delete large volumes of data. This qualifies as Destructive with high severity given the potential blast radius of wiping large amounts of cached media.
From the tool's definition pruning of cached remote media older than N days... lets operators force an aggressive pass
Attacks that exploit this kind of access
The rule that runs mastodon_media_prune safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Crow, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For mastodon_media_prune, this is the rule to start with:
mastodon_media_prune is removed from the agent's tool list entirely, so the agent never calls it. The rest of the server keeps working.
The button opens the PolicyLayer dashboard: create your workspace, connect Crow, apply this rule, and every mastodon_media_prune call is checked against it from then on.
Questions about mastodon_media_prune
Manually trigger pruning of cached remote media older than N days. The sidekiq scheduler handles this on a recurring cadence (MEDIA_CACHE_RETENTION_PERIOD env); this lets operators force an aggressive pass. Rate-limited: 2/hour. It is categorised as a Destructive tool in the Crow MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Crow MCP server in PolicyLayer and add a rule for mastodon_media_prune: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Crow. Nothing to install.
mastodon_media_prune is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the mastodon_media_prune rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for mastodon_media_prune. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
mastodon_media_prune is provided by the Crow MCP server (kh0pper/crow). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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