Get running timer

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

With no annotations provided, the description carries the full behavioral burden. It discloses genuinely useful behaviors: the result is conditional ('if any'), the response includes an inactivity hint derived from .clockify/config.yml when configured, and the config_root parameter depends on the MCP's scoping mode. However, it does not explicitly state the operation is read-only, does not describe failure/error behavior, and leaves the return shape undefined. The description adds value beyond the name but does not fully cover the behavioral burden.

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 tightly-packed sentences with zero filler. The first sentence front-loads the core purpose, and the second provides a single practical usage caveat. Every word earns its place, and it is appropriately sized for the tool's simplicity.

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 simple getter with two optional parameters and full schema coverage, the description covers the essentials: what is returned, the conditional empty result, and the config-related dependency. The one notable gap is that without an output schema, the description does not outline the structure of the returned timer object, which could cause some ambiguity for an agent trying to interpret the result. This is a minor gap given the overall clarity.

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%, providing a strong baseline of 3. The description goes slightly further by clarifying the condition under which config_root should be supplied ('when this MCP is user-scoped'), linking the parameter to a runtime context that the schema alone does not fully address. The workspace_id parameter is not discussed in the description, but the schema's 'Workspace ID override.' is already adequate, so no compensation is required.

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 states a specific verb ('Returns'), a specific resource ('the currently running timer'), and a scope ('for the user, if any'). The 'if any' qualifier adds precision about the empty case, and the tool is clearly distinguishable from siblings like clockify_start_timer (mutation), clockify_stop_timer (mutation), and clockify_list_time_entries (historical list) by its read-only 'currently running' semantics.

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?

Usage context is implied rather than stated: an agent must infer to call this tool when it needs the current active timer. The description does provide a practical usage hint about when to pass config_root ('when this MCP is user-scoped'), but it offers no explicit when-not conditions or alternatives compared to clockify_list_time_entries or clockify_today_summary. The 'if any' phrasing does give a mild exclusionary signal (returns none when nothing is running).

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