chats_add_participant

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

Annotations already declare readOnlyHint=false, destructiveHint=true, and openWorldHint=true, so the mutation and external-visibility profile is covered. The description adds a useful confirmation requirement, but the 'deletes, or redirects data' clause is inapplicable boilerplate for an additive operation and adds no real behavioral detail.

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 core action is front-loaded in the first sentence, and the endpoint/gRPC/socket footer is compact. The second sentence is generic warning boilerplate rather than task-specific guidance, so it earns its place less clearly.

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?

No output schema exists and nothing is said about the result of the mutation, and parameter meaning is left entirely to the schema's sparse examples. Annotations cover the safety profile, so the definition is minimally viable but leaves an agent guessing about ID semantics and outcome.

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 0% across three required parameters (chatId, channelId, participantId) that carry only example values. The description says nothing about what these IDs are, their format, or the chatId/channelId relationship, so it fails to compensate for the coverage gap.

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+resource ('Add a participant to a chat'), which is unambiguous and implicitly contrasts with the sibling chats_remove_participant. It does not explicitly name the inverse sibling or scope, so it falls short of a 5.

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?

Provides a prerequisite ('get the user's confirmation first') for an action that reaches other people, but the warning reads as generic boilerplate ('deletes, or redirects data') that does not apply to adding a participant. No alternatives or when-not-to-use conditions are given relative to chats_remove_participant or chats_get_participants.

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