MCP tools reference

Authentication, tools, parameters, and error handling for the Gamma MCP server.

Complete reference for the Gamma MCP server's authentication, available tools, input parameters, and error handling.

Quick reference

• All requests require an OAuth 2.0 Bearer token.

• Three tools: generate, get_themes, get_folders.

• OAuth discovery via RFC 9728 at /.well-known/oauth-protected-resource.

• Dynamic Client Registration supported via RFC 7591.

• Errors return { "error": "...", "isError": true }.

Authentication

The Gamma MCP server uses OAuth 2.0. Every request must include a valid Bearer token.

Authorization header

Include your token with each request:

Authorization: Bearer <your-oauth-token>

OAuth discovery

The server implements RFC 9728 (OAuth Protected Resource Metadata). Clients retrieve OAuth configuration at:

GET /.well-known/oauth-protected-resource

Dynamic client registration

The authorization server supports RFC 7591 Dynamic Client Registration. Discover the registration endpoint URL from the authorization server metadata obtained via the OAuth discovery endpoint above.

Authentication errors

A failed authentication returns 401 Unauthorized with a WWW-Authenticate header:

WWW-Authenticate: Bearer resource_metadata="https://<server>/.well-known/oauth-protected-resource"

Use the resource_metadata URI to discover the authorization server and initiate the OAuth flow.

Tools overview

Tool	Description	Read-only	Destructive	Idempotent
generate	Create presentations, documents, webpages, or social posts	No	No	No
get_themes	Browse or search the Gamma theme library	Yes	No	Yes
get_folders	Browse or search your Gamma folders	Yes	No	Yes

generate

Create a new presentation, document, webpage, or social media post. Ask the user clarifying questions about text mode, length, tone, and audience when needed.

Each call creates new content — the tool is not idempotent.

Input parameters

Parameter	Type	Required	Description
inputText	string	Yes	Content to generate from — a text prompt, outline, or full content
textMode	enum	No	How to handle input text: generate (new content from brief prompt), condense (summarize existing content), preserve (use content as-is)
format	enum	No	Output type: presentation, document, social, webpage
numCards	int	No	Number of slides, cards, or pages to generate
themeId	string	No	Theme ID from get_themes
folderIds	array[string]	No	Folder IDs from get_folders to organize the content
additionalInstructions	string	No	Extra guidance for the AI generator not covered by other parameters
exportAs	enum	No	Export format: pptx or pdf (only when the user explicitly requests export)

Text options

Optional textOptions object for controlling text generation.

Parameter	Type	Description
amount	enum	Text density per slide or section: brief, medium, detailed, extensive
tone	string	Writing tone (e.g., professional, casual)
audience	string	Target audience (e.g., executives, students)
language	string	Language code (e.g., en, es, fr)

Image options

Optional imageOptions object for controlling image sourcing.

Parameter	Type	Description
source	enum	Image source: aiGenerated, webAllImages, webFreeToUse, webFreeToUseCommercially, pictographic, giphy, unsplash, placeholder, noImages
model	string	AI image model (only when source is aiGenerated)
style	string	Style for AI images (e.g., photorealistic, illustration)

Card options

Optional cardOptions object for layout and header/footer configuration.

Parameter	Type	Description
dimensions	enum	Aspect ratio or page size: 16x9, 4x3, fluid, letter, a4, pageless, 1x1, 4x5, 9x16
headerFooter	object	Header and footer configuration (only use if explicitly requested)

Header/footer object

The headerFooter object contains six slot positions and two visibility flags. All properties are optional.

Parameter	Type	Description
topLeft	object	Top-left header slot
topCenter	object	Top-center header slot
topRight	object	Top-right header slot
bottomLeft	object	Bottom-left footer slot
bottomCenter	object	Bottom-center footer slot
bottomRight	object	Bottom-right footer slot
hideFromFirstCard	boolean	Hide header/footer from the first card
hideFromLastCard	boolean	Hide header/footer from the last card

Slot configuration

Each slot object (topLeft, topCenter, etc.) accepts:

Parameter	Type	Required	Description
type	enum	Yes	Content type: cardNumber, image, text
source	enum	No	Image source (required when type is image): themeLogo, custom
src	string	No	Image URL (required when type is image and source is custom)
value	string	No	Text content (required when type is text)
size	enum	No	Image size: sm, md, lg, xl

Sharing options

Optional sharingOptions object for controlling access after generation.

Parameter	Type	Description
workspaceAccess	enum	Workspace member access: edit, comment, view, noAccess, fullAccess
externalAccess	enum	External user access: edit, comment, view, noAccess
emailOptions	object	Share via email to specific recipients (see below)

Email options object

Parameter	Type	Required	Description
recipients	array[string]	Yes	Email addresses to share with
access	enum	Yes	Recipient access level: edit, comment, view, fullAccess

Output

Field	Type	Description
generationId	string	Unique ID for the generation
status	enum	Generation status: completed or failed
gammaUrl	string	URL to the created content (when status is completed)
exportUrl	string	Download URL for the export file (when exportAs was specified)
credits.deducted	int	Credits deducted for this generation
credits.remaining	int	Remaining credits after generation
error	string	Error message (when status is failed)

get_themes

Browse or search the Gamma theme library. Use the returned id in the generate tool's themeId parameter.

If the user references a theme by name, search by name. Otherwise, fetch the full list and choose based on tone and color keywords.

Input parameters

Parameter	Type	Description
name	string	Optional. Search themes by name (only when the user references a specific theme name)

Output

Field	Type	Description
themes	array[object]	Array of theme objects
themes[].id	string	Theme ID to pass to generate
themes[].name	string	Display name
themes[].type	enum	standard or custom
themes[].colorKeywords	array[string]	Color keywords describing the palette
themes[].toneKeywords	array[string]	Tone keywords describing the style
count	int	Total themes returned

get_folders

Browse or search your Gamma folders. Use the returned id in the generate tool's folderIds parameter.

Input parameters

Parameter	Type	Description
name	string	Optional. Search folders by name (omit to return all folders)

Output

Field	Type	Description
folders	array[object]	Array of folder objects
folders[].id	string	Folder ID to pass to generate
folders[].name	string	Display name
count	int	Total folders returned

Error handling

All tools return errors in a consistent format:

Error response

{
  "error": "Error message describing what went wrong",
  "isError": true
}

Error	Description
401 Unauthorized	Missing or invalid OAuth Bearer token — see Authentication errors
Invalid parameter values	One or more parameters do not match expected format or values
Rate limit exceeded	Too many requests in a given time period
Network connectivity	Unable to establish connection to the server
Insufficient credits	Account does not have enough credits to complete the generation

Related

• Set up the MCP server for getting started and troubleshooting

• Connect integrations for platform-specific setup

• Generate from text for the equivalent REST API parameters

• Access and pricing for credit costs and plan details