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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds genuinely new behavioral context: newest-first ordering, album collapsing to a single row, and the resulting effect that a page may contain fewer than `limit` posts.

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 dense sentences, front-loaded with what the tool returns and followed by the accepted inputs and the album/limit caveat. No filler sentences, though the return-field enumeration is somewhat long given an output schema exists.

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?

With six parameters, only one required, an output schema present and a read-only annotation set, the description covers inputs, ordering, and the one surprising edge case (album collapse shortening pages). It is essentially complete for calling the tool; only the sibling-routing guidance is absent.

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 83%, so the schema already documents channel, query, since, until and message_type in detail. The description adds only the collapsed-album caveat around `limit` and a loose restatement of channel/query/time-range, so it does not materially extend parameter meaning.

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 ('Recent posts from a tracked Telegram channel, newest first') and enumerates the returned metrics, which is far more than a restatement of the name. It does not explicitly contrast itself with close siblings such as get_channel_timeline or search, so sibling differentiation is left to inference.

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 lists the optional query and time-range filters, which implies how to narrow results, but never states when to prefer this tool over get_channel_timeline or search, nor any exclusion criteria. Usage is implied rather than directed.

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