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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and openWorld, so the safety profile is covered. The description adds genuine context beyond that: the checks run against public DNS, MTA-STS and BIMI are informational only ("tájékoztatásul"), and results arrive with Hungarian explanations and remediation tips calibrated to the 2024 Gmail/Yahoo sender rules. It stops short of disclosing failure behavior (unreachable/missing records, timeouts) or any limits on query volume.

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 front-loaded sentence that leads with the motivating question, then the mechanism, then the output. The parenthetical enumerations ("darabszám, szintaxis, +all/?all, 10 lekérdezéses korlát") are dense but each item carries real information. Slightly long, yet no sentence is filler.

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 one-parameter, read-only tool with no output schema, the description covers what is inspected and what the response contains (Hungarian explanation plus fix tips), which is what an agent needs to decide and to report results. Missing only edge-case behavior for malformed or record-less domains.

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% and the single parameter already documents that a bare domain or a full email address (info@cegem.hu) is accepted. The description restates that same duality ("Egy domain (vagy e-mail-cím)") without adding syntax, normalization, or validation semantics. Baseline 3 applies since the schema does the heavy lifting.

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 (ellenőrzi) and resource (a domain or email address's public DNS records) and then enumerates exactly which records it inspects: MX, SPF, DMARC, DKIM, MTA-STS, BIMI. No sibling tool (tax, HR, legal calculators) overlaps, and an agent can tell instantly this is a DNS-based email deliverability audit rather than a generic validator.

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 opening question ("Miért kerülnek spambe egy cég levelei?") frames the use case clearly: diagnosing spam placement / sender-authentication problems. It does not, however, state prerequisites (the domain must have public DNS records), what to do if records are absent, or any explicit exclusion. Clear context without exclusions, hence 4.

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