diff --git a/.cspell.json b/.cspell.json
index c78b966..43040b8 100644
--- a/.cspell.json
+++ b/.cspell.json
@@ -26,7 +26,8 @@
     "voyageai",
     "vectordump",
     "payloadobject",
-    "markdownit"
+    "markdownit",
+    "plpgsql"
   ],
   "dictionaries": ["typescript", "node", "software-terms"],
   "import": ["@cspell/dict-typescript/cspell-ext.json", "@cspell/dict-node/cspell-ext.json", "@cspell/dict-software-terms"],
diff --git a/src/adapters/supabase/helpers/issues.ts b/src/adapters/supabase/helpers/issues.ts
index 063d8a9..5f30821 100644
--- a/src/adapters/supabase/helpers/issues.ts
+++ b/src/adapters/supabase/helpers/issues.ts
@@ -3,14 +3,10 @@ import { SuperSupabase } from "./supabase";
 import { Context } from "../../../types/context";
 import { markdownToPlainText } from "../../utils/markdown-to-plaintext";
 
-export interface IssueType {
-  id: string;
-  markdown?: string;
-  author_id: number;
-  created_at: string;
-  modified_at: string;
-  payloadObject: Record<string, unknown> | null;
-  embedding: number[];
+export interface IssueSimilaritySearchResult {
+  issue_id: string;
+  issue_plaintext: string;
+  similarity: number;
 }
 
 export class Issues extends SuperSupabase {
@@ -70,15 +66,13 @@ export class Issues extends SuperSupabase {
     }
   }
 
-  async findSimilarIssues(markdown: string, threshold: number): Promise<IssueType[] | null> {
+  async findSimilarIssues(markdown: string, threshold: number, currentId: string): Promise<IssueSimilaritySearchResult[] | null> {
     const embedding = await this.context.adapters.voyage.embedding.createEmbedding(markdown);
-    const { data, error } = await this.supabase
-      .from("issues")
-      .select("*")
-      .eq("type", "issue")
-      .textSearch("embedding", embedding.join(","))
-      .order("embedding", { foreignTable: "issues", ascending: false })
-      .lte("embedding", threshold);
+    const { data, error } = await this.supabase.rpc("find_similar_issues", {
+      current_id: currentId,
+      query_embedding: embedding,
+      threshold: threshold,
+    });
     if (error) {
       this.context.logger.error("Error finding similar issues", error);
       return [];
diff --git a/src/handlers/issue-deduplication.ts b/src/handlers/issue-deduplication.ts
new file mode 100644
index 0000000..2378a1e
--- /dev/null
+++ b/src/handlers/issue-deduplication.ts
@@ -0,0 +1,111 @@
+import { IssueSimilaritySearchResult } from "../adapters/supabase/helpers/issues";
+import { Context } from "../types";
+import { IssuePayload } from "../types/payload";
+
+export interface IssueGraphqlResponse {
+  node: {
+    title: string;
+    url: string;
+  };
+  similarity: string;
+}
+
+/**
+ * Check if an issue is similar to any existing issues in the database
+ * @param context
+ * @returns true if the issue is similar to an existing issue, false otherwise
+ */
+export async function issueChecker(context: Context): Promise<boolean> {
+  const {
+    logger,
+    adapters: { supabase },
+    octokit,
+  } = context;
+  const { payload } = context as { payload: IssuePayload };
+  const issue = payload.issue;
+  const issueContent = issue.body + issue.title;
+
+  // Fetch all similar issues based on settings.warningThreshold
+  const similarIssues = await supabase.issue.findSimilarIssues(issueContent, context.config.warningThreshold, issue.node_id);
+  console.log(similarIssues);
+  if (similarIssues && similarIssues.length > 0) {
+    const matchIssues = similarIssues.filter((issue) => issue.similarity >= context.config.matchThreshold);
+
+    // Handle issues that match the MATCH_THRESHOLD (Very Similar)
+    if (matchIssues.length > 0) {
+      logger.info(`Similar issue which matches more than ${context.config.matchThreshold} already exists`);
+      await octokit.issues.update({
+        owner: payload.repository.owner.login,
+        repo: payload.repository.name,
+        issue_number: issue.number,
+        state: "closed",
+        state_reason: "not_planned",
+      });
+    }
+
+    // Handle issues that match the settings.warningThreshold but not the MATCH_THRESHOLD
+    if (similarIssues.length > 0) {
+      logger.info(`Similar issue which matches more than ${context.config.warningThreshold} already exists`);
+      await handleSimilarIssuesComment(context, payload, issue.number, similarIssues);
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/**
+ * Handle commenting on an issue with similar issues information
+ * @param context
+ * @param payload
+ * @param issueNumber
+ * @param similarIssues
+ */
+async function handleSimilarIssuesComment(context: Context, payload: IssuePayload, issueNumber: number, similarIssues: IssueSimilaritySearchResult[]) {
+  const issueList: IssueGraphqlResponse[] = await Promise.all(
+    similarIssues.map(async (issue: IssueSimilaritySearchResult) => {
+      const issueUrl: IssueGraphqlResponse = await context.octokit.graphql(
+        `query($issueNodeId: ID!) {
+          node(id: $issueNodeId) {
+            ... on Issue {
+              title
+              url
+            }
+          }
+        }`,
+        { issueNodeId: issue.issue_id }
+      );
+      issueUrl.similarity = (issue.similarity * 100).toFixed(2);
+      return issueUrl;
+    })
+  );
+
+  const commentBody = issueList.map((issue) => `- [${issue.node.title}](${issue.node.url}) Similarity: ${issue.similarity}`).join("\n");
+  const body = `This issue seems to be similar to the following issue(s):\n\n${commentBody}`;
+
+  const existingComments = await context.octokit.issues.listComments({
+    owner: payload.repository.owner.login,
+    repo: payload.repository.name,
+    issue_number: issueNumber,
+  });
+
+  const existingComment = existingComments.data.find(
+    (comment) => comment.body && comment.body.includes("This issue seems to be similar to the following issue(s)")
+  );
+
+  if (existingComment) {
+    await context.octokit.issues.updateComment({
+      owner: payload.repository.owner.login,
+      repo: payload.repository.name,
+      comment_id: existingComment.id,
+      body: body,
+    });
+  } else {
+    await context.octokit.issues.createComment({
+      owner: payload.repository.owner.login,
+      repo: payload.repository.name,
+      issue_number: issueNumber,
+      body: body,
+    });
+  }
+}
diff --git a/src/plugin.ts b/src/plugin.ts
index 2f7dad8..0d0876c 100644
--- a/src/plugin.ts
+++ b/src/plugin.ts
@@ -13,6 +13,7 @@ import { VoyageAIClient } from "voyageai";
 import { deleteIssues } from "./handlers/delete-issue";
 import { addIssue } from "./handlers/add-issue";
 import { updateIssue } from "./handlers/update-issue";
+import { issueChecker } from "./handlers/issue-deduplication";
 
 /**
  * The main plugin function. Split for easier testing.
@@ -31,11 +32,13 @@ export async function runPlugin(context: Context) {
   } else if (isIssueEvent(context)) {
     switch (eventName) {
       case "issues.opened":
+        await issueChecker(context);
         return await addIssue(context);
-      case "issues.deleted":
-        return await deleteIssues(context);
       case "issues.edited":
+        await issueChecker(context);
         return await updateIssue(context);
+      case "issues.deleted":
+        return await deleteIssues(context);
     }
   } else {
     logger.error(`Unsupported event: ${eventName}`);
diff --git a/src/types/database.ts b/src/types/database.ts
index 3622f52..f741570 100644
--- a/src/types/database.ts
+++ b/src/types/database.ts
@@ -1,31 +1,6 @@
 export type Json = string | number | boolean | null | { [key: string]: Json | undefined } | Json[];
 
 export type Database = {
-  graphql_public: {
-    Tables: {
-      [_ in never]: never;
-    };
-    Views: {
-      [_ in never]: never;
-    };
-    Functions: {
-      graphql: {
-        Args: {
-          operationName?: string;
-          query?: string;
-          variables?: Json;
-          extensions?: Json;
-        };
-        Returns: Json;
-      };
-    };
-    Enums: {
-      [_ in never]: never;
-    };
-    CompositeTypes: {
-      [_ in never]: never;
-    };
-  };
   public: {
     Tables: {
       issue_comments: {
@@ -240,321 +215,6 @@ export type Database = {
       [_ in never]: never;
     };
   };
-  storage: {
-    Tables: {
-      buckets: {
-        Row: {
-          allowed_mime_types: string[] | null;
-          avif_autodetection: boolean | null;
-          created_at: string | null;
-          file_size_limit: number | null;
-          id: string;
-          name: string;
-          owner: string | null;
-          owner_id: string | null;
-          public: boolean | null;
-          updated_at: string | null;
-        };
-        Insert: {
-          allowed_mime_types?: string[] | null;
-          avif_autodetection?: boolean | null;
-          created_at?: string | null;
-          file_size_limit?: number | null;
-          id: string;
-          name: string;
-          owner?: string | null;
-          owner_id?: string | null;
-          public?: boolean | null;
-          updated_at?: string | null;
-        };
-        Update: {
-          allowed_mime_types?: string[] | null;
-          avif_autodetection?: boolean | null;
-          created_at?: string | null;
-          file_size_limit?: number | null;
-          id?: string;
-          name?: string;
-          owner?: string | null;
-          owner_id?: string | null;
-          public?: boolean | null;
-          updated_at?: string | null;
-        };
-        Relationships: [];
-      };
-      migrations: {
-        Row: {
-          executed_at: string | null;
-          hash: string;
-          id: number;
-          name: string;
-        };
-        Insert: {
-          executed_at?: string | null;
-          hash: string;
-          id: number;
-          name: string;
-        };
-        Update: {
-          executed_at?: string | null;
-          hash?: string;
-          id?: number;
-          name?: string;
-        };
-        Relationships: [];
-      };
-      objects: {
-        Row: {
-          bucket_id: string | null;
-          created_at: string | null;
-          id: string;
-          last_accessed_at: string | null;
-          metadata: Json | null;
-          name: string | null;
-          owner: string | null;
-          owner_id: string | null;
-          path_tokens: string[] | null;
-          updated_at: string | null;
-          user_metadata: Json | null;
-          version: string | null;
-        };
-        Insert: {
-          bucket_id?: string | null;
-          created_at?: string | null;
-          id?: string;
-          last_accessed_at?: string | null;
-          metadata?: Json | null;
-          name?: string | null;
-          owner?: string | null;
-          owner_id?: string | null;
-          path_tokens?: string[] | null;
-          updated_at?: string | null;
-          user_metadata?: Json | null;
-          version?: string | null;
-        };
-        Update: {
-          bucket_id?: string | null;
-          created_at?: string | null;
-          id?: string;
-          last_accessed_at?: string | null;
-          metadata?: Json | null;
-          name?: string | null;
-          owner?: string | null;
-          owner_id?: string | null;
-          path_tokens?: string[] | null;
-          updated_at?: string | null;
-          user_metadata?: Json | null;
-          version?: string | null;
-        };
-        Relationships: [
-          {
-            foreignKeyName: "objects_bucketId_fkey";
-            columns: ["bucket_id"];
-            isOneToOne: false;
-            referencedRelation: "buckets";
-            referencedColumns: ["id"];
-          },
-        ];
-      };
-      s3_multipart_uploads: {
-        Row: {
-          bucket_id: string;
-          created_at: string;
-          id: string;
-          in_progress_size: number;
-          key: string;
-          owner_id: string | null;
-          upload_signature: string;
-          user_metadata: Json | null;
-          version: string;
-        };
-        Insert: {
-          bucket_id: string;
-          created_at?: string;
-          id: string;
-          in_progress_size?: number;
-          key: string;
-          owner_id?: string | null;
-          upload_signature: string;
-          user_metadata?: Json | null;
-          version: string;
-        };
-        Update: {
-          bucket_id?: string;
-          created_at?: string;
-          id?: string;
-          in_progress_size?: number;
-          key?: string;
-          owner_id?: string | null;
-          upload_signature?: string;
-          user_metadata?: Json | null;
-          version?: string;
-        };
-        Relationships: [
-          {
-            foreignKeyName: "s3_multipart_uploads_bucket_id_fkey";
-            columns: ["bucket_id"];
-            isOneToOne: false;
-            referencedRelation: "buckets";
-            referencedColumns: ["id"];
-          },
-        ];
-      };
-      s3_multipart_uploads_parts: {
-        Row: {
-          bucket_id: string;
-          created_at: string;
-          etag: string;
-          id: string;
-          key: string;
-          owner_id: string | null;
-          part_number: number;
-          size: number;
-          upload_id: string;
-          version: string;
-        };
-        Insert: {
-          bucket_id: string;
-          created_at?: string;
-          etag: string;
-          id?: string;
-          key: string;
-          owner_id?: string | null;
-          part_number: number;
-          size?: number;
-          upload_id: string;
-          version: string;
-        };
-        Update: {
-          bucket_id?: string;
-          created_at?: string;
-          etag?: string;
-          id?: string;
-          key?: string;
-          owner_id?: string | null;
-          part_number?: number;
-          size?: number;
-          upload_id?: string;
-          version?: string;
-        };
-        Relationships: [
-          {
-            foreignKeyName: "s3_multipart_uploads_parts_bucket_id_fkey";
-            columns: ["bucket_id"];
-            isOneToOne: false;
-            referencedRelation: "buckets";
-            referencedColumns: ["id"];
-          },
-          {
-            foreignKeyName: "s3_multipart_uploads_parts_upload_id_fkey";
-            columns: ["upload_id"];
-            isOneToOne: false;
-            referencedRelation: "s3_multipart_uploads";
-            referencedColumns: ["id"];
-          },
-        ];
-      };
-    };
-    Views: {
-      [_ in never]: never;
-    };
-    Functions: {
-      can_insert_object: {
-        Args: {
-          bucketid: string;
-          name: string;
-          owner: string;
-          metadata: Json;
-        };
-        Returns: undefined;
-      };
-      extension: {
-        Args: {
-          name: string;
-        };
-        Returns: string;
-      };
-      filename: {
-        Args: {
-          name: string;
-        };
-        Returns: string;
-      };
-      foldername: {
-        Args: {
-          name: string;
-        };
-        Returns: string[];
-      };
-      get_size_by_bucket: {
-        Args: Record<PropertyKey, never>;
-        Returns: {
-          size: number;
-          bucket_id: string;
-        }[];
-      };
-      list_multipart_uploads_with_delimiter: {
-        Args: {
-          bucket_id: string;
-          prefix_param: string;
-          delimiter_param: string;
-          max_keys?: number;
-          next_key_token?: string;
-          next_upload_token?: string;
-        };
-        Returns: {
-          key: string;
-          id: string;
-          created_at: string;
-        }[];
-      };
-      list_objects_with_delimiter: {
-        Args: {
-          bucket_id: string;
-          prefix_param: string;
-          delimiter_param: string;
-          max_keys?: number;
-          start_after?: string;
-          next_token?: string;
-        };
-        Returns: {
-          name: string;
-          id: string;
-          metadata: Json;
-          updated_at: string;
-        }[];
-      };
-      operation: {
-        Args: Record<PropertyKey, never>;
-        Returns: string;
-      };
-      search: {
-        Args: {
-          prefix: string;
-          bucketname: string;
-          limits?: number;
-          levels?: number;
-          offsets?: number;
-          search?: string;
-          sortcolumn?: string;
-          sortorder?: string;
-        };
-        Returns: {
-          name: string;
-          id: string;
-          updated_at: string;
-          created_at: string;
-          last_accessed_at: string;
-          metadata: Json;
-        }[];
-      };
-    };
-    Enums: {
-      [_ in never]: never;
-    };
-    CompositeTypes: {
-      [_ in never]: never;
-    };
-  };
 };
 
 type PublicSchema = Database[Extract<keyof Database, "public">];
diff --git a/src/types/plugin-inputs.ts b/src/types/plugin-inputs.ts
index 77a40f9..a942db2 100644
--- a/src/types/plugin-inputs.ts
+++ b/src/types/plugin-inputs.ts
@@ -18,7 +18,13 @@ export interface PluginInputs<T extends SupportedEventsU = SupportedEventsU, TU
  * The kernel will extract those and pass them to the plugin,
  * which are built into the context object from setup().
  */
-export const pluginSettingsSchema = T.Object({});
+export const pluginSettingsSchema = T.Object(
+  {
+    matchThreshold: T.Number(),
+    warningThreshold: T.Number(),
+  },
+  { default: { matchThreshold: 0.95, warningThreshold: 0.75 } }
+);
 
 export const pluginSettingsValidator = new StandardValidator(pluginSettingsSchema);
 
diff --git a/supabase/migrations/20240913145445_issue_comments.sql b/supabase/migrations/20240913145445_issue_comments.sql
new file mode 100644
index 0000000..1753ab1
--- /dev/null
+++ b/supabase/migrations/20240913145445_issue_comments.sql
@@ -0,0 +1,13 @@
+CREATE OR REPLACE FUNCTION find_similar_issues(current_id VARCHAR, query_embedding vector(1024), threshold float8)
+RETURNS TABLE(issue_id VARCHAR, issue_plaintext TEXT, similarity float8) AS $$
+BEGIN
+  RETURN QUERY
+  SELECT id AS issue_id,
+         plaintext AS issue_plaintext,
+         1 - (embedding <=> query_embedding) AS similarity
+  FROM issues
+  WHERE id <> current_id
+    AND 1 - (embedding <=> query_embedding) >= threshold
+  ORDER BY similarity DESC;
+END;
+$$ LANGUAGE plpgsql;
diff --git a/tests/main.test.ts b/tests/main.test.ts
index 40eeb7f..a8c14b8 100644
--- a/tests/main.test.ts
+++ b/tests/main.test.ts
@@ -163,7 +163,10 @@ function createContextInner(
       installation: { id: 1 } as Context["payload"]["installation"],
       organization: { login: STRINGS.USER_1 } as Context["payload"]["organization"],
     } as Context["payload"],
-    config: {},
+    config: {
+      warningThreshold: 0.75,
+      matchThreshold: 0.95,
+    },
     adapters: {} as Context["adapters"],
     logger: new Logs("debug"),
     env: {} as Env,