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

Annotations already establish readOnly, idempotent, non-destructive, and closed-world behavior, so the bar is low. The description still adds a real behavioral constraint not present in structured data: results are limited to channels/groups/chats the *authorized* user can manage, which tells the agent to expect a permission-filtered, potentially empty result and that no auth escalation is described.

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?

A single sentence with no filler, front-loaded with the usage cue followed by the resource and scope. Nothing is wasted, but the sentence is thin enough that its brevity reflects limited content rather than tight editing.

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 zero-parameter, read-only listing tool with an output schema present and full annotation coverage, the description supplies everything needed: what is listed, and the permission scope of the listing. Return values are correctly delegated to the output schema.

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 tool takes zero parameters, which sets the baseline at 4. The schema is empty with additionalProperties false, and the description correctly adds no parameter guidance because none is needed, though it also supplies no filtering options the agent might expect (there are none).

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 names a specific verb ("list") and a concrete resource ("Telegram channels, groups, and chats"), and adds scope the tool name alone does not convey: only assets the authorized user can manage through Postlyra. That scope distinguishes it clearly from the post/publication/template siblings, though it does not explicitly reference any sibling by name.

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?

"Use this when you need to list..." identifies the triggering scenario but the condition is essentially a restatement of the tool's function. There is no statement of when not to use it or which sibling covers adjacent needs (e.g., listing publications vs. channels), so usage is only implied rather than routed.

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