Create a Message changedapi/beta/messages/create
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Lines−264removed
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21
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First seen
14 Aug 2026
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Recorded edits20to this page, all time
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from line 21
2121
2222 - `string`
2323
24 - `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 45 more`
24 - `"message-batches-2024-09-24"`
2525
26 - `"message-batches-2024-09-24"`
26 - `"prompt-caching-2024-07-31"`
2727
28 - `"prompt-caching-2024-07-31"`
28 - `"computer-use-2024-10-22"`
2929
30 - `"computer-use-2024-10-22"`
30 - `"computer-use-2025-01-24"`
3131
32 - `"computer-use-2025-01-24"`
32 - `"pdfs-2024-09-25"`
3333
34 - `"pdfs-2024-09-25"`
34 - `"token-counting-2024-11-01"`
3535
36 - `"token-counting-2024-11-01"`
36 - `"token-efficient-tools-2025-02-19"`
3737
38 - `"token-efficient-tools-2025-02-19"`
38 - `"output-128k-2025-02-19"`
3939
40 - `"output-128k-2025-02-19"`
40 - `"files-api-2025-04-14"`
4141
42 - `"files-api-2025-04-14"`
42 - `"mcp-client-2025-04-04"`
4343
44 - `"mcp-client-2025-04-04"`
44 - `"mcp-client-2025-11-20"`
4545
46 - `"mcp-client-2025-11-20"`
46 - `"dev-full-thinking-2025-05-14"`
4747
48 - `"dev-full-thinking-2025-05-14"`
48 - `"interleaved-thinking-2025-05-14"`
4949
50 - `"interleaved-thinking-2025-05-14"`
50 - `"code-execution-2025-05-22"`
5151
52 - `"code-execution-2025-05-22"`
52 - `"extended-cache-ttl-2025-04-11"`
5353
54 - `"extended-cache-ttl-2025-04-11"`
54 - `"context-1m-2025-08-07"`
5555
56 - `"context-1m-2025-08-07"`
56 - `"context-management-2025-06-27"`
5757
58 - `"context-management-2025-06-27"`
58 - `"model-context-window-exceeded-2025-08-26"`
5959
60 - `"model-context-window-exceeded-2025-08-26"`
60 - `"skills-2025-10-02"`
6161
62 - `"skills-2025-10-02"`
62 - `"fast-mode-2026-02-01"`
6363
64 - `"fast-mode-2026-02-01"`
64 - `"output-300k-2026-03-24"`
6565
66 - `"output-300k-2026-03-24"`
66 - `"user-profiles-2026-03-24"`
6767
68 - `"user-profiles-2026-03-24"`
68 - `"user-profiles-2026-08-18"`
6969
70 - `"user-profiles-2026-08-18"`
70 - `"user-profiles-2026-09-04"`
7171
72 - `"user-profiles-2026-09-04"`
72 - `"advisor-tool-2026-03-01"`
7373
74 - `"advisor-tool-2026-03-01"`
74 - `"managed-agents-2026-04-01"`
7575
76 - `"managed-agents-2026-04-01"`
76 - `"cache-diagnosis-2026-04-07"`
7777
78 - `"cache-diagnosis-2026-04-07"`
78 - `"dreaming-2026-04-21"`
7979
80 - `"dreaming-2026-04-21"`
80 - `"thinking-token-count-2026-05-13"`
8181
82 - `"thinking-token-count-2026-05-13"`
82 - `"server-side-fallback-2026-06-01"`
8383
84 - `"server-side-fallback-2026-06-01"`
84 - `"server-side-fallback-2026-07-01"`
8585
86 - `"server-side-fallback-2026-07-01"`
86 - `"fallback-credit-2026-06-01"`
8787
88 - `"fallback-credit-2026-06-01"`
88 - `"fallback-credit-2026-07-01"`
8989
90 - `"fallback-credit-2026-07-01"`
90 - `"agent-memory-2026-07-22"`
9191
92 - `"agent-memory-2026-07-22"`
92 - `"mid-conversation-tool-changes-2026-07-01"`
9393
94 - `"mid-conversation-tool-changes-2026-07-01"`
94 - `"compact-2026-01-12"`
9595
96 - `"compact-2026-01-12"`
96 - `"computer-use-2025-11-24"`
9797
98 - `"computer-use-2025-11-24"`
98 - `"mcp-tunnels-2026-06-22"`
9999
100 - `"mcp-tunnels-2026-06-22"`
100 - `"structured-outputs-2025-11-13"`
101101
102 - `"structured-outputs-2025-11-13"`
102 - `"task-budgets-2026-03-13"`
103103
104 - `"task-budgets-2026-03-13"`
104 - `"thinking-display-updates-2026-08-18"`
105105
106 - `"thinking-display-updates-2026-08-18"`
106 - `"ce-user-management-2026-07-13"`
107107
108 - `"ce-user-management-2026-07-13"`
108 - `"mid-conversation-output-config-2026-07-01"`
109109
110 - `"mid-conversation-output-config-2026-07-01"`
110 - `"thinking-binding-controls-2026-08-01"`
111111
112 - `"thinking-binding-controls-2026-08-01"`
112 - `"mid-conversation-system-clear-at-2026-08-21"`
113113
114 - `"mid-conversation-system-clear-at-2026-08-21"`
114 - `"compact-2026-09-04"`
115115
116 - `"compact-2026-09-04"`
116 - `"inline-tools-2026-09-15"`
117117
118 - `"inline-tools-2026-09-15"`
118 - `"mcp-client-2026-09-15"`
119119
120 - `"mcp-client-2026-09-15"`
121
122120- `"anthropic-user-profile-id": optional string`
123121
124122 The user profile ID to attribute this request to. Use when acting on behalf of a party other than your organization. Requires the `user-profiles` beta header.
from line 3100
31023100
31033101 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
31043102
3105 - `"claude-sonnet-5-5" or "claude-fable-5-1" or "claude-opus-5-5" or 16 more`
3103 - `"claude-sonnet-5-5"`
31063104
3107 The model that will complete your prompt.
3105 Efficient model for coding and agents
31083106
3109 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
3107 - `"claude-fable-5-1"`
31103108
3111 - `"claude-sonnet-5-5"`
3109 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
31123110
3113 Efficient model for coding and agents
3111 - `"claude-opus-5-5"`
31143112
3115 - `"claude-fable-5-1"`
3113 Powerful intelligence for coding, knowledge work, and long-running agents
31163114
3117 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
3115 - `"claude-mythos-5-1"`
31183116
3119 - `"claude-opus-5-5"`
3117 Our most capable model for cybersecurity and biology research, available through trusted access programs
31203118
3121 Powerful intelligence for coding, knowledge work, and long-running agents
3119 - `"claude-sonnet-5"`
31223120
3123 - `"claude-mythos-5-1"`
3121 Efficient model for coding and agents
31243122
3125 Our most capable model for cybersecurity and biology research, available through trusted access programs
3123 - `"claude-fable-5"`
31263124
3127 - `"claude-sonnet-5"`
3125 Next generation of intelligence for the hardest knowledge work and coding problems
31283126
3129 Efficient model for coding and agents
3127 - `"claude-mythos-5"`
31303128
3131 - `"claude-fable-5"`
3129 Most capable model for cybersecurity and biology research
31323130
3133 Next generation of intelligence for the hardest knowledge work and coding problems
3131 - `"claude-opus-5"`
31343132
3135 - `"claude-mythos-5"`
3133 Powerful intelligence for long-running agents and coding
31363134
3137 Most capable model for cybersecurity and biology research
3135 - `"claude-opus-4-8"`
31383136
3139 - `"claude-opus-5"`
3137 Powerful intelligence for long-running agents and coding
31403138
3141 Powerful intelligence for long-running agents and coding
3139 - `"claude-opus-4-7"`
31423140
3143 - `"claude-opus-4-8"`
3141 Powerful intelligence for long-running agents and coding
31443142
3145 Powerful intelligence for long-running agents and coding
3143 - `"claude-opus-4-6"`
31463144
3147 - `"claude-opus-4-7"`
3145 Powerful intelligence for long-running agents and coding
31483146
3149 Powerful intelligence for long-running agents and coding
3147 - `"claude-sonnet-4-6"`
31503148
3151 - `"claude-opus-4-6"`
3149 Best combination of speed and intelligence
31523150
3153 Powerful intelligence for long-running agents and coding
3151 - `"claude-haiku-4-5"`
31543152
3155 - `"claude-sonnet-4-6"`
3153 Fastest model with near-frontier intelligence
31563154
3157 Best combination of speed and intelligence
3155 - `"claude-haiku-4-5-20251001"`
31583156
3159 - `"claude-haiku-4-5"`
3157 Fastest model with near-frontier intelligence
31603158
3161 Fastest model with near-frontier intelligence
3159 - `"claude-opus-4-5"`
31623160
3163 - `"claude-haiku-4-5-20251001"`
3161 Powerful intelligence for long-running agents and coding
31643162
3165 Fastest model with near-frontier intelligence
3163 - `"claude-opus-4-5-20251101"`
31663164
3167 - `"claude-opus-4-5"`
3165 Powerful intelligence for long-running agents and coding
31683166
3169 Powerful intelligence for long-running agents and coding
3167 - `"claude-sonnet-4-5"`
31703168
3171 - `"claude-opus-4-5-20251101"`
3169 High-performance model for agents and coding
31723170
3173 Powerful intelligence for long-running agents and coding
3171 - `"claude-sonnet-4-5-20250929"`
31743172
3175 - `"claude-sonnet-4-5"`
3173 High-performance model for agents and coding
31763174
3177 High-performance model for agents and coding
3175 - `"claude-mythos-preview"`
31783176
3179 - `"claude-sonnet-4-5-20250929"`
3177 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
31803178
3181 High-performance model for agents and coding
3179 New class of intelligence, strongest in coding and cybersecurity
31823180
3183 - `"claude-mythos-preview"`
3184
3185 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
3186
3187 New class of intelligence, strongest in coding and cybersecurity
3188
31893181 - `string`
31903182
31913183 - `name: "advisor"`
from line 3878
38863878
38873879 - `"updates"`
38883880
3889 - `Default = "default"`
3881 - `"default"`
38903882
38913883- `inference_geo: optional string or null`
38923884
from line 6962
69706962
69716963 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
69726964
6973 - `"claude-sonnet-5-5" or "claude-fable-5-1" or "claude-opus-5-5" or 16 more`
6965 - `"claude-sonnet-5-5"`
69746966
6975 The model that will complete your prompt.
6967 Efficient model for coding and agents
69766968
6977 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
6969 - `"claude-fable-5-1"`
69786970
6979 - `"claude-sonnet-5-5"`
6971 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
69806972
6981 Efficient model for coding and agents
6973 - `"claude-opus-5-5"`
69826974
6983 - `"claude-fable-5-1"`
6975 Powerful intelligence for coding, knowledge work, and long-running agents
69846976
6985 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
6977 - `"claude-mythos-5-1"`
69866978
6987 - `"claude-opus-5-5"`
6979 Our most capable model for cybersecurity and biology research, available through trusted access programs
69886980
6989 Powerful intelligence for coding, knowledge work, and long-running agents
6981 - `"claude-sonnet-5"`
69906982
6991 - `"claude-mythos-5-1"`
6983 Efficient model for coding and agents
69926984
6993 Our most capable model for cybersecurity and biology research, available through trusted access programs
6985 - `"claude-fable-5"`
69946986
6995 - `"claude-sonnet-5"`
6987 Next generation of intelligence for the hardest knowledge work and coding problems
69966988
6997 Efficient model for coding and agents
6989 - `"claude-mythos-5"`
69986990
6999 - `"claude-fable-5"`
6991 Most capable model for cybersecurity and biology research
70006992
7001 Next generation of intelligence for the hardest knowledge work and coding problems
6993 - `"claude-opus-5"`
70026994
7003 - `"claude-mythos-5"`
6995 Powerful intelligence for long-running agents and coding
70046996
7005 Most capable model for cybersecurity and biology research
6997 - `"claude-opus-4-8"`
70066998
7007 - `"claude-opus-5"`
6999 Powerful intelligence for long-running agents and coding
70087000
7009 Powerful intelligence for long-running agents and coding
7001 - `"claude-opus-4-7"`
70107002
7011 - `"claude-opus-4-8"`
7003 Powerful intelligence for long-running agents and coding
70127004
7013 Powerful intelligence for long-running agents and coding
7005 - `"claude-opus-4-6"`
70147006
7015 - `"claude-opus-4-7"`
7007 Powerful intelligence for long-running agents and coding
70167008
7017 Powerful intelligence for long-running agents and coding
7009 - `"claude-sonnet-4-6"`
70187010
7019 - `"claude-opus-4-6"`
7011 Best combination of speed and intelligence
70207012
7021 Powerful intelligence for long-running agents and coding
7013 - `"claude-haiku-4-5"`
70227014
7023 - `"claude-sonnet-4-6"`
7015 Fastest model with near-frontier intelligence
70247016
7025 Best combination of speed and intelligence
7017 - `"claude-haiku-4-5-20251001"`
70267018
7027 - `"claude-haiku-4-5"`
7019 Fastest model with near-frontier intelligence
70287020
7029 Fastest model with near-frontier intelligence
7021 - `"claude-opus-4-5"`
70307022
7031 - `"claude-haiku-4-5-20251001"`
7023 Powerful intelligence for long-running agents and coding
70327024
7033 Fastest model with near-frontier intelligence
7025 - `"claude-opus-4-5-20251101"`
70347026
7035 - `"claude-opus-4-5"`
7027 Powerful intelligence for long-running agents and coding
70367028
7037 Powerful intelligence for long-running agents and coding
7029 - `"claude-sonnet-4-5"`
70387030
7039 - `"claude-opus-4-5-20251101"`
7031 High-performance model for agents and coding
70407032
7041 Powerful intelligence for long-running agents and coding
7033 - `"claude-sonnet-4-5-20250929"`
70427034
7043 - `"claude-sonnet-4-5"`
7035 High-performance model for agents and coding
70447036
7045 High-performance model for agents and coding
7037 - `"claude-mythos-preview"`
70467038
7047 - `"claude-sonnet-4-5-20250929"`
7039 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
70487040
7049 High-performance model for agents and coding
7041 New class of intelligence, strongest in coding and cybersecurity
70507042
7051 - `"claude-mythos-preview"`
7052
7053 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
7054
7055 New class of intelligence, strongest in coding and cybersecurity
7056
70577043 - `string`
70587044
70597045 - `name: "advisor"`
from line 7187
72017187
72027188 - `default_config: optional BetaMCPToolDefaultConfig`
72037189
7204 Default configuration applied to all tools from this serve
7190 Default configuration applied to all tools from this server
7191
7192 - `defer_loading: optional boolean`
7193
7194 - `enabled: optional boolean`
7195
7196 - `tools: optional array of BetaMCPToolParam or null`
7197
7198 The server's tool listing, pinned: when present, the server is not asked for its tools before sampling and exactly these entries, with `default_config` and `configs` applied, are the toolset's tools. Copy it from the `mcp_tool_listing` block of an earlier response.
7199
7200 - `input_schema: map[unknown]`
7201
7202 The tool's input schema as the MCP server lists it, verbatim.
7203
7204 - `name: string`
7205
7206 The tool's name as the MCP server lists it (not prefixed with the server name).
7207
7208 minLength: 1
7209
7210 - `description: optional string or null`
7211
7212 The tool's description as the MCP server lists it.
7213
7214 - `BetaResponseToolRem
No line in this hunk matches that.