diff --git a/doc/SSID_API_Manual_Test_Plans.md b/doc/SSID_API_Manual_Test_Plans.md
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+This document details manual test cases used during the development of SSID API. The test cases are described using `curl` commands, but similar API clients might be used for manual testing such as Postman or HTTP libraries of different languages/ frameworks. For more details, you may trace back to PRs in which those features were developed.
+
+
+## POST `/api/v1/courses/{course_id}/assignment`
+This route is for creating a new assignment for SSID to process.
+
+#### 1. Successful, should return {"assignmentID": 1168}
+
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/2008/assignments/" \
+ -H "X-API-KEY: SSID_API_KEY" \
+ -F title=assignment1 \
+ -F language=java \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip
+```
+
+#### 2. {"error": "Value of {parameterName} is not valid. {state the constraint/ limit}"
+
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/2008/assignments/" \
+ -H "X-API-KEY: SSID_API_KEY" \
+ -F title=assignment2 \
+ -F language=cpp17 \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip
+```
+
+#### 3. {"error" : "Missing required parameter {parameterName}"}
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/2008/assignments/" \
+ -H "X-API-KEY: SSID_API_KEY" \
+ -F language=java \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip
+```
+
+#### 4. {"error" : "Parameter {parameterName} is invalid or not yet supported."}
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/2008/assignments/" \
+ -H "X-API-KEY: SSID_API_KEY" \
+ -F title=assignment4 \
+ -F language=java \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip \
+ -F sensitivity=100
+```
+
+#### 5. {"error" : "Missing or invalid API key."}
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/2008/assignments/" \
+ -H "X-API-KEY: EVIL_API_KEY" \
+ -F title=assignment5 \
+ -F language=java \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip
+```
+
+#### 6. Successful with csv mapping, should return {"assignmentID": 1168}, csv mapping working
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/2008/assignments/" \
+ -H "X-API-KEY: SSID_API_KEY" \
+ -F title=assignment6 \
+ -F language=java \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip \
+ -F mappingFile=@csv_mapping.csv 
+```
+
+#### 7. Successful with past semesters as references, should return {"assignmentID": 1168}, references are correctly processed
+```
+curl -i \
+ -X POST "http://localhost:3000/api/v1/courses/3471/assignments/" \
+ -H "X-API-KEY: SSID_API_KEY" \
+ -F title=assignment1 \
+ -F language=java \
+ -F sizeOfNGram=5 \
+ -F studentSubmissions=@cs1101_a1.zip \
+ -F references=@references.zip
+```
+
+## GET `/api/v1/assignments/{assignment_id}/submission_similarities/`
+This route is for getting all submission similarities of an assignment.
+
+```
+curl -i \
+ -X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/" \
+ -H "X-API-KEY: SSID_API_KEY"
+```
+#### 1. Successful
+```
+curl -i \
+ -X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/" \
+ -H "X-API-KEY: SSID_API_KEY"
+```
+#### 2. {"error":"Missing or invalid API key."}                          
+```
+curl -i \
+ -X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/1540892" \
+ -H "X-API-KEY: EVIL_API_KEY"
+```
+
+#### 3. With threshold
+```
+curl -i \
+ -X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities?threshold=95" \
+ -H "X-API-KEY: SSID_API_KEY"
+```
+
+#### 4. With limit
+```
+curl -i \
+ -X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities?limit=5" \
+ -H "X-API-KEY: SSID_API_KEY"
+```
+
+#### 5. With page
+```
+curl -i \
+ -X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities?page=2" \
+ -H "X-API-KEY: SSID_API_KEY"
+```
+
+## GET `/api/v1/assignments/{assignment_id}/submission_similarities/{submission_similarities_id}`
+
+This route is for getting details of a pair of flagged submissions.
+
+#### 1. Successful
+```
+curl -i \
+-X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/1549986" \
+-H "X-API-KEY: SSID_API_KEY"
+```
+
+#### 2. {"error":"Submission similarities requested do not exist."}
+```
+curl -i \
+-X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/9999999" \
+-H "X-API-KEY: SSID_API_KEY"
+```
+
+#### 3. {"error":"Missing or invalid API key."}
+```
+curl -i \
+-X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/1549986" \
+-H "X-API-KEY: EVIL_API_KEY"
+```
+
+## GET `/api/v1/assignments/{assignment_id}/submission_similarities/{submission_similarity_id}/view_pdf`
+This route is for getting a minimalist PDF report for a pair of flagged student submissions.
+
+#### 1. Successful PDF Generation
+```
+curl -i \
+-X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/1549986/view_pdf" \
+-H "X-API-KEY: SSID_API_KEY"
+```
+
+#### 2. {"error":"Submission similarities requested do not exist."}
+```
+curl -i \
+-X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/9999999/view_pdf" \
+-H "X-API-KEY: SSID_API_KEY"
+```
+
+#### 3. {"error":"Missing or invalid API key."}
+```
+curl -i \
+-X GET "http://localhost:3000/api/v1/assignments/3018/submission_similarities/1549986/view_pdf" \
+-H "X-API-KEY: EVIL_API_KEY"
+```
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