telegram_sub_add

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

With no annotations, the description carries the full burden. It discloses key behavior: no subscriptions means listen to ALL, and once a principal has any subscription, only those chats are pushed. This covers important side effects, though it does not detail every edge case (e.g., duplicate subscriptions, overwrite semantics).

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 concise and well-structured, covering the main behavior in a few sentences without excessive verbosity. The back-compat note and principal usage are included efficiently.

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?

The description provides sufficient context for the tool's primary use case and its behavioral implications. It does not include return value details, but with no output schema defined, that is not required. Overall, an agent can understand when and why to use this tool.

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?

The schema has 5 parameters but only chat_id and principal are described in the text. mode, note, and title have no explanation in the description, leaving their purpose and acceptable values unclear. With only 40% schema coverage, the description fails to add meaning for most parameters.

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 action (subscribe a principal's Telegram listener to a chat) and the resource (chat with admin allow-list). It also explains the back-compat behavior and the use of 'principal' to assign for another user, making the purpose specific and 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?

The description explains the core behavior and mentions 'Use principal to assign for another user,' but it does not explicitly contrast with sibling tools like telegram_sub_list or telegram_sub_remove. The guidance on when to use this tool versus alternatives is implied rather than stated.

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