health_check

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

With only readOnlyHint provided, the description carries the behavioral load and does so richly: it discloses that any JSON error from the plugin (including 403) counts as reachable, that only Jira's HTML 404 or a network failure counts as unreachable, and that the tool itself fails only when Jira is unreachable or rejects credentials. It also describes the return shape, well beyond what the annotation provides.

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 tight sentences, front-loaded with the primary check before the conditional plugin check. Every clause earns its place — the error-classification rules are exactly what an agent needs to interpret results, and the return summary is compact.

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?

There is no output schema, so the description appropriately documents the returned object (ok, jiraUser, baseUrl, zephyrPluginReachable) and the condition under which zephyrPluginReachable is omitted. Combined with the error semantics, an agent has everything needed to call and interpret this tool.

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 tool takes no parameters, so there are no argument semantics to document; the schema is empty with additionalProperties false. Baseline 4 applies since no parameter explanation is needed.

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+resource — verify connectivity and credentials via GET /rest/api/2/myself, plus optional Zephyr plugin reachability on /rest/atm/1.0. This is clearly a diagnostic tool, distinct from siblings like jira_get_current_user (which fetches the user) or jira_server_info (which returns server metadata).

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 explains the tool's operating conditions (only checks the plugin when ZEPHYR_DEFAULT_PROJECT_KEY is set) and failure conditions, which gives useful context. However, it never explicitly says when to reach for this tool versus alternatives such as jira_request or jira_get_current_user — the diagnostic use case is only implied.

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