telegram_join_chatJoin a public Telegram channel or group by @username or invite link. Adds your personal account to chats so you can read, send, search, and manage messages.
Join a public channel/group by @username or invite link.
| Name | Required | Description | Default |
|---|---|---|---|
| target | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false (a state-changing, non-reversible membership mutation) and openWorldHint=true, so the agent knows it touches the outside world. The description adds the 'public' restriction and input form but says nothing about failure behavior (invalid link, already joined, rate limits) or what the call returns.
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?
One short sentence with the verb front-loaded and the accepted input formats packed into the same clause. No redundancy or filler.
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 one-parameter mutation with no output schema, the definition covers the essentials but leaves out meaningfully relevant context: whether the join is idempotent, what happens on invalid/expired links, and whether a chat identifier is returned for follow-up calls.
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 0% and the single 'target' property is documented only as a bare string with minLength 1. The description compensates well by stating the accepted value forms ('@username or invite link'), which is exactly the semantic an agent needs to construct the argument.
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 (join) and resource (public channel/group), and the qualifier 'public' plus '@username or invite link' distinguishes it meaningfully from telegram_leave_chat. It does not explicitly name a sibling to avoid, but the action is unambiguous.
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?
'by @username or invite link' implies the accepted inputs and the scope is limited to public channels/groups, which is useful context. However, it gives no exclusions (e.g., private groups requiring an invite, already-a-member cases) and does not point to any alternative tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.