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

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so the description mainly needs to add context. The phrase «ещё одну сессию» usefully signals additive behavior — an existing profile gains another session rather than being replaced — which corroborates the non-idempotent hint. It says nothing about what happens on an expired/invalid token or whether re-linking an already-linked session is an error.

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 with the action first and the prerequisites in parentheses; nothing is padding. The nested parentheticals make it slightly dense but every clause carries information.

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 two-param mutation tool with no output schema and only half the parameters documented, the description omits where session_id comes from and what the call returns or how failures surface. It covers the happy path precondition but leaves an agent guessing on the remaining call-shaping details.

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 50%: access_token is fully documented in the schema (7-day validity, don't expose to the user) and the description only echoes its source. session_id has no schema description at all, and the description only implies it is a diagnostic session identifier without stating where it is obtained (diagnostic_start / deep_dive_start). Baseline 3 fits, but the uncovered parameter is not fully compensated for.

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?

Names a specific verb (привязать / link) and a specific resource (a diagnostic session — basic or deep-dive) to an already-confirmed profile. It distinguishes itself from the token-issuing siblings by pointing at ruforge_profile_check/confirm as the token source, though it doesn't explicitly contrast with ruforge_profile_history or lookup.

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?

States a precondition — the profile must already be confirmed and the access_token must come from ruforge_profile_check/confirm — which is real usage context. However, it never says when to call this versus alternatives (e.g. when to start a new session instead), and offers no exclusions or failure conditions.

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