create_group

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

Despite no annotations, the description discloses key behavioral traits: the creator becomes admin, all listed members receive an invitation notification, and the tool returns the group's ID and invite link. It does not mention any potential limits or side effects, but overall adequately covers the immediate effects.

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?

The description is two sentences, concise and front-loaded with the primary action, then additional details. Every sentence adds value without redundancy.

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?

Given there are three simple parameters (no nested objects, no enums) and no output schema, the description adequately covers the tool's complete behavior: creation, admin assignment, notifications, return values, and references to related tools. No gaps.

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 description coverage is 100%, and the description adds minimal semantic value beyond the schema. The schema already describes 'name', 'members' (with phone numbers), and 'description' as optional. The description reiterates these in natural language but does not add new meaning.

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?

The description clearly states the tool's purpose: 'Create a new Signal group with specified members.' It also specifies that the creator is automatically admin, members receive invitations, and returns the new group's ID and invite link. Distinguishes from siblings like update_group and send_group_message by mentioning their specific use cases after creation.

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?

The description explicitly guides when to use this tool (creating a group) and when to use alternatives: 'Use update_group to modify the group after creation... Use send_group_message to post messages to the group.' This provides clear context and prevents misuse.

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