Avito Self-Check

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

The description goes well beyond the annotations by explaining the precise drift criteria: 403 firewall blocks and CDP-down are inconclusive transport states, while only a reached-200 JSON body failing the parse smoke counts as drift. This is exactly the non-obvious behavioral context an agent needs.

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 description is well-structured and front-loads the core purpose and tri-state result, with important edge-case semantics following. The return-format section is slightly redundant given an output schema exists, but it does not meaningfully bloat the definition.

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 no-input read-only diagnostic with output schema and safety annotations provided, the description covers everything material: what it probes, how to interpret success, drift, and inconclusive results, and a return-format summary. No critical operational detail is missing.

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, and the input schema is an empty closed object, so there is no parameter semantics burden. The description does not introduce any parameter-related ambiguity; the baseline for zero-parameter tools 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?

The description states a specific purpose: a structural drift canary for Avito that runs live probes against search, card, and seller endpoints. It also names the tri-state result, making it clearly distinguishable from data-fetching siblings like avito_search, avito_card, and avito_seller.

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 selfcheck/canary framing implies when the tool should be used, and the probe targets are explicit. However, the description never directly says 'use this to verify Avito connector health instead of fetching marketplace data,' nor does it exclude scenarios or name alternatives.

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