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

Beyond the readOnly/openWorld annotations, it usefully discloses the unauthenticated widget-based access model and the public-only limitation. But the cost disclosure contradicts itself — 'at least 10 Nexscope credits' in one sentence and '1 credit per request' a few sentences later — and the cache paragraph is pasted verbatim from the schema, so the agent is left uncertain about what a call actually costs.

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 first two sentences are well front-loaded, but the remainder is bloated with scraped marketing copy ('Telegram Post Details API View Pricing', 'Get one public Telegram post by URL') and a verbatim duplicate of the cache parameter documentation, including the markdown link. The redundant and conflicting credit statements add noise rather than clarity.

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 two-parameter lookup with no output schema, the description gives an adequate field-level picture of the response and covers the auth and access constraints. The only meaningful gap is the unresolved credit cost, which matters for an agent deciding whether to retry or use caching.

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 100%, so both `url` and the `cache_max_age` enum are already fully documented in the schema. The description adds no additional meaning about accepted URL forms (e.g. t.me/s/… vs t.me/…), so it neither compensates nor regresses against the baseline.

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?

Opens with a specific verb and resource ('Retrieves one public Telegram post') and enumerates the payload fields (text, publish date, views, reactions, forward source, media/link previews), which clearly separates it from listing-style siblings such as social_telegram_channel_posts. It never names an alternative tool, so differentiation is inferred from the singular 'one post by URL' framing rather than stated.

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 scope constraint 'Private and invite-only posts are not supported' plus 'public post widget without a logged-in account' tells the agent which inputs will work, which is real guidance. However, there is no explicit when-to-use or when-to-use-something-else statement (e.g. use this vs. channel_posts for enumerating a channel's feed), so routing to siblings is left implicit.

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