avito_unread_count

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered and the bar is lower. The description adds one useful behavioral fact: the value comes from Avito's own counter rather than a locally computed tally, which hints at possible staleness, but it says nothing about scope (whole account vs per-ad), rate limits, or refresh cadence.

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-loading the verb and resource, then qualifying the data source. Nothing is redundant with the schema or annotations.

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-argument read counter this is nearly complete; the main residual gap is that no output schema exists and the description never says what the count is returned as (a bare number, an object with conversation vs message breakdowns). The rest — scope, data source, safety profile — is adequately covered.

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, so per the rubric the baseline is 4. There is nothing for the description to clarify beyond the implicit scope of "du compte Avito connecté".

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 ("Compte") and resource ("conversations/messages non lus du compte Avito"), making it clearly a count rather than a listing tool. It is distinguishable from avito_list_conversations and avito_mark_read by the word "Compte", though it never names those siblings explicitly.

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?

Usage is only implied: an agent can infer this is the tool for checking an unread badge before deciding to list or mark conversations. There is no explicit when-to-use statement, no mention of alternatives like avito_list_conversations, and no preconditions (e.g., must be logged in).

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