discord_create_thread

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=false, idempotentHint=false and openWorldHint=true, so the safety profile is partly covered. The description adds genuinely new context: the specific bot permissions required (Create Public/Private Threads, Send Messages, View Channel, Embed Links) and retry guidance ('check the result before retrying'). It does repeat non-idempotency already in annotations, which keeps it from a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core action and the type semantics, then permissions and the mutation warning. It is a single dense paragraph with no wasted sentences, though the type enumeration is somewhat long and could be tightened.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 9-parameter mutation tool with nested message objects, the description covers type semantics, the forum/media message requirement, permissions, and non-idempotency. An output schema exists so return values need not be explained. Minor gaps remain around invitable/applied_tags applicability, but the essentials are present.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds meaning beyond the schema: it clarifies the type default (12 when omitted) and the conditional requirement of message for forum/media channels. These are behavioral constraints on parameters rather than restatements.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Create a new thread') and immediately scopes it against the sibling discord_create_thread_from_message by saying 'without a starter message', plus covers the forum/media post variant. An agent can distinguish this from the from-message sibling without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear conditional guidance: use message when creating a post in forum or media channels, and explains which thread types apply to which parent channel types. It does not explicitly name the alternative tool (create_thread_from_message) as the choice when a starter message exists, so it stops short of full when/when-not routing.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.