jira_issue_update_tool

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

Without annotations, the description bears the full burden. It discloses that only provided fields are updated (partial update behavior) and that custom fields are validated against the project schema. This is good, but it omits potential side-effects like required permissions or immutability of certain fields.

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 sentences: the first states the purpose, the second adds two key behavioral notes. Every word earns its place, no redundancy.

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?

Given the complexity (8 parameters, output schema exists), the description is reasonably complete. It covers partial update behavior and custom field validation. The output schema covers return values, so no need to describe them. It could mention label behavior (replace vs append) but that is in the schema. Overall adequate.

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?

The input schema covers 88% of parameters with individual descriptions. The description adds no parameter-specific meaning beyond the schema, except the implicit behavioral note that only provided fields are updated. The custom_fields parameter lacks a description in both schema and description, but the description mentions validation.

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 clearly states 'Update an existing Jira issue', which is a specific verb+resource combination. It distinguishes from sibling tools like jira_issue_create_tool and jira_issue_get_tool.

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 description provides clear context for when to use the tool (update existing issues) and includes the note 'Only provided fields are updated', which implies partial updates. However, it does not explicitly exclude alternatives or mention when not to use it (e.g., for status changes, which would use jira_workflow_transition_tool).

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