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

With no annotations, the description carries the full load and does disclose key traits: no auth/account requirement, public data source, and the kinds of values returned (subscriber counts, categories, trust scores). It says nothing about rate limits, result ordering, pagination behavior, or whether results are cached/stale, which matters for a tool capped at 25 results.

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?

Three tight sentences, front-loaded with what the tool searches and how large the corpus is, then the differentiating no-account fact, then the parameter hint. No filler and nothing redundant.

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 read-only catalog search with no output schema, the description is nearly sufficient: it identifies the data source, the return fields, the auth model, and the filtering knob. It leaves result ordering and pagination/limits implicit, but those are minor for this tool's complexity.

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 100%, so the schema already documents all three parameters including the type enum and limit bounds. The description adds only a small hint ('use type to restrict to one entity kind') that largely restates the schema, so the baseline 3 applies.

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 and resource ('full-text search over the tgden catalog') and scopes it precisely with catalog size and entity types (channels, group chats, bots). It implicitly separates itself from search_posts and channel_stats by describing the catalog rather than posts or a single channel, but it never names a sibling to sharpen the boundary.

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?

Gives clear usage context: it works without a Telegram account and surfaces communities the user has NOT joined, which tells an agent when this discovery tool is the right pick over account-scoped tools. It offers no explicit exclusions or named alternatives, so the agent must still infer when search_posts or best_channels_by_category would be better.

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