Update Issue Checklist Item

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

Beyond the readOnlyHint=false annotation, the description discloses the patch-like behavior ('Only the fields you pass change'), the null semantics, the clearing behavior, and the return value ('Returns the whole checklist'). This gives an agent a solid mental model of the mutation without relying solely on the schema.

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 sentences with no filler. The first sentence says what the tool does and its main use cases; the second explains key behavioral semantics; the third points to the ID source and return value. Every sentence earns its place and the most important information is 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?

For an 8-parameter update tool with a rich schema and output schema, the description covers all essential operational context: partial-update semantics, null handling, clearing values, ID sourcing, and the return value. Required parameters and field-level constraints are already in the schema, so nothing critical 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?

Schema coverage is 100%, so the baseline is 3. The description adds value by synthesizing the optional-parameter behavior: null leaves fields unchanged, clear flags remove values, and checklist_item_id is sourced from issue_get_checklist. This clarifies how the parameters relate beyond their individual descriptions.

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 names a specific action ('Update one checklist item'), the resource ('of a Yandex Tracker issue'), and concrete use cases ('check it off, rename it, or set an assignee or a deadline'). This clearly differentiates it from sibling tools like issue_add_checklist_items, issue_delete_checklist_item, and issue_get_checklist.

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?

It clearly states when to use the tool: to update an existing checklist item rather than add or delete one. It also tells the user where item ids come from ('issue_get_checklist') and explains when to use clear_assignee/clear_deadline. It does not explicitly name the alternative add/delete siblings, but the update-focused context makes the intended usage clear.

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