Function checkPermissions

source code/tools/SkillTool/SkillTool.ts:434–580

(
    { skill, args },
    context,
  )

  },

  async checkPermissions(
    { skill, args },
    context,
  ): Promise<PermissionDecision> {
    // Skills are just skill names, no arguments
    const trimmed = skill.trim()

    // Remove leading slash if present (for compatibility)
    const commandName = trimmed.startsWith('/') ? trimmed.substring(1) : trimmed

    const appState = context.getAppState()
    const permissionContext = appState.toolPermissionContext

    // Look up the command object to pass as metadata
    const commands = await getAllCommands(context)
    const commandObj = findCommand(commandName, commands)

    // Helper function to check if a rule matches the skill
    // Normalizes both inputs by stripping leading slashes for consistent matching
    const ruleMatches = (ruleContent: string): boolean => {
      // Normalize rule content by stripping leading slash
      const normalizedRule = ruleContent.startsWith('/')
        ? ruleContent.substring(1)
        : ruleContent

      // Check exact match (using normalized commandName)
      if (normalizedRule === commandName) {
        return true
      }
      // Check prefix match (e.g., "review:*" matches "review-pr 123")
      if (normalizedRule.endsWith(':*')) {
        const prefix = normalizedRule.slice(0, -2) // Remove ':*'
        return commandName.startsWith(prefix)
      }
      return false
    }

    // Check for deny rules
    const denyRules = getRuleByContentsForTool(
      permissionContext,
      SkillTool as Tool,
      'deny',
    )
    for (const [ruleContent, rule] of denyRules.entries()) {
      if (ruleMatches(ruleContent)) {
        return {
          behavior: 'deny',
          message: `Skill execution blocked by permission rules`,
          decisionReason: {
            type: 'rule',
            rule,
          },
        }
      }
    }

    // Remote canonical skills are ant-only experimental — auto-grant.
    // Placed AFTER the deny loop so a user-configured Skill(_canonical_:*)