Change the context library's tag prefix and re-tag every Bear note that currently uses the old prefix. Sub-tags are preserved — #context/research becomes #<new>/research. Updates both the markdown body and the CloudKit tag index, and persists the new prefix to the context config. Useful when alig...
Risk signalsBulk/mass operation — affects multiple targets
Part of the Better Bear server.
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AI agents use bear_context_set_prefix to create or modify resources in Better Bear. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call bear_context_set_prefix repeatedly, creating or modifying resources faster than any human could review. PolicyLayer's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Better Bear.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
{
"version": "1",
"default": "deny",
"tools": {
"bear_context_set_prefix": {
"limits": [
{
"counter": "bear_context_set_prefix_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}See the full Better Bear policy for all 35 tools.
These attack patterns abuse exactly the kind of access bear_context_set_prefix gives an agent. Each links to the full case and the policy that stops it:
Other write tools across the catalogue. The same approach applies to each: rate-limit and validate the arguments.
Change the context library's tag prefix and re-tag every Bear note that currently uses the old prefix. Sub-tags are preserved — #context/research becomes #<new>/research. Updates both the markdown body and the CloudKit tag index, and persists the new prefix to the context config. Useful when aligning the qualifier tag with a broader naming scheme like Johnny Decimal (e.g. '10-projects'). Run bear_context_sync afterwards to refresh the library.. It is categorised as a Write tool in the Better Bear MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Better Bear MCP server in PolicyLayer and add a rule for bear_context_set_prefix: 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 Better Bear. Nothing to install.
bear_context_set_prefix is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the bear_context_set_prefix 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 bear_context_set_prefix. 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.
bear_context_set_prefix is provided by the Better Bear MCP server (better-bear). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 35 Better Bear tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
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