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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and a closed-world scope, so the safety profile is covered. The description adds genuine behavioral value by enumerating the counter fields returned (recipients, sent, failed, skipped, pending), which matters because there is no output schema. It does not cover not-found behavior or what happens if neither identifier resolves.

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?

Two compact clauses, the read-only marker and the resource are front-loaded, and every phrase carries information (counters listed, id provenance given). No filler or restated title text.

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 simple two-parameter read with no output schema, the description covers the return payload and where the identifier comes from, which is most of what an agent needs. The remaining gap is the required-parameter/error case, which is minor for a lookup tool but not stated.

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%, so the description must compensate, and it does explain the provenance of campaign_id and the campaign_uuid alternative. However, both parameters are optional with null defaults and the description never states that at least one is required or what precedence applies if both are supplied, leaving a real ambiguity for the caller.

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 and resource ("[read] One Telegram campaign") and immediately scopes it to a single campaign with its counters, which cleanly separates it from the sibling list_tg_campaigns. An agent can tell exactly what this returns without opening the schema.

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?

It gives concrete routing guidance: take campaign_id from list_tg_campaigns' tg_campaign_id, or pass campaign_uuid instead. That is clear context for when and how to call it, though it never explicitly says when to prefer this over list_tg_campaign_recipients or similar siblings.

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