yandex_login

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

No annotations are provided, so the description carries the full burden. It usefully discloses that the output is a link to show the user and that no terminal is required, but it omits other behavioral facts an agent would want: whether calling again invalidates a prior link, whether it waits for confirmation, and what happens on failure. Adequate but incomplete for an unannotated flow tool.

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?

Three short sentences, front-loaded with the action and its output, then the hand-off instruction. Every sentence earns its place with no 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?

No output schema exists, but the description does explain what is returned (an authorization link for the user) and the next step. For a 2-parameter, all-optional login-initiation tool this is nearly complete; only session/error semantics are left unstated.

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% – both 'mode' (manual vs localhost, including the Redirect URI prerequisite) and 'services' are fully documented in the schema. The description adds no parameter meaning beyond that, so the baseline 3 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?

States a specific verb and resource ('Step 1 of Yandex login: returns an authorization link') and names the exact follow-up sibling (yandex_submit_code). An agent can distinguish this login-initiation tool from yandex_auth_status and yandex_submit_code without opening any schema.

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 'Step 1' framing plus 'after confirmation call yandex_submit_code' gives clear sequencing context for the login flow. It does not, however, mention checking yandex_auth_status first or state any condition under which this tool should not be used, so it stops short of explicit when-not guidance.

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