Yandex Metrika: read export file

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description still adds real behavior the annotations don't: the 32 KiB ceiling and that chunks are cut on line boundaries, which matters for parsing. It stops short of explaining cursor exhaustion or whether an empty chunk signals end-of-file.

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 short sentences, zero filler. The chunking behavior leads and the input constraint follows immediately, so the most decision-relevant facts are front-loaded.

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?

An output schema exists, so return values and next_cursor needn't be re-explained, and the annotations carry the safety profile. What remains thin is the termination/pagination lifecycle across successive calls, which for a chunked reader is the one thing an agent most needs stated.

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%, so the baseline is 3; the description earns above that by clarifying the identifier semantics ('never a path or URL'), which prevents a plausible misuse the pattern/regex alone doesn't rule out. It adds nothing about cursor or max_bytes, but the schema documents those well.

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 ('Reads a finished Yandex Metrika export file') plus the chunking unit, and explicitly rules out the common wrong input ('never a path or URL'). That constraint alone separates it from siblings like metrika_get_job or metrika_export_report.

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 implied rather than stated: the chunk/cursor framing tells an agent this is a paginated read, and the schema notes artifact_id comes from metrika_get_job, but the description itself never says 'use after the job finishes' or names an alternative. An agent must infer the sequencing from structured fields.

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