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

The annotations already declare this as read-only and open-world, and the description adds a useful behavioral detail: it returns a plain message when no timer is running. This provides transparency about the empty-result case without contradicting the annotations.

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?

The description is two concise sentences with no redundant wording. The core purpose is front-loaded, and the empty-state behavior is stated efficiently.

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 tool's simplicity, zero parameters, read-only annotations, and clear description covering both running and not-running states, nothing meaningful is missing for an agent to select and invoke this tool correctly.

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 has zero parameters, so parameter semantics are not a concern. The baseline of 4 applies because there is nothing for the description to add beyond the empty schema.

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 uses a specific verb ('Show'), a clear resource ('currently running Clockify timer'), and adds useful detail ('with elapsed time so far'). This clearly distinguishes it from sibling tools like start_timer, stop_timer, and list_time_entries.

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 intended use is implied by the name and description: call this when you need the active timer's status. However, there is no explicit guidance about when to prefer this over alternatives, nor any exclusions mentioned.

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

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

The readOnlyHint annotation is present and the description adds filter behavior (active by default) without contradiction. It does not mention output fields or pagination, but the read-only nature is already annotated.

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 concise sentences deliver the purpose, usage, and filter behavior without redundant wording.

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?

While no output schema is provided, the description is sufficient for an agent to know the tool lists projects, returns projectId, and applies filters. Minor gap: it does not describe the response structure, but this is common for list endpoints.

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 schema covers both parameters with descriptions, and the description adds extra context for includeArchived ('Active projects only unless...'), but the name filter semantics are not further expanded.

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 it lists projects in the Clockify workspace and explicitly connects to the projectId needed by start_timer and log_time, distinguishing it from sibling tools.

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 explicitly says 'Use this to find the projectId needed by start_timer and log_time' and clarifies the archived filter behavior with 'Active projects only unless includeArchived is set.'

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

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

The annotations already declare readOnlyHint=true and openWorldHint=true, so the read-only nature is covered. The description adds no new behavioral details beyond the list scope and intended consumer, which is acceptable but not rich.

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?

The description is a single sentence with no filler. It front-loads the core action and immediately gives the practical reason to use the tool.

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 zero-parameter read-only list tool, this description is complete. It states what is listed, where, and why the result is needed. No output schema is present, but the description gives enough context for an agent to call and use the result correctly.

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 has zero parameters, so the input schema is trivially complete. The description adds useful semantic context about how the returned tags relate to the tagIds argument in start_timer/log_time.

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 the specific action ('List tags'), the scope ('in the workspace'), and the intended purpose ('for the tagIds argument of start_timer / log_time'). This clearly distinguishes it from sibling tools like list_projects and list_tasks.

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 gives explicit context for when to use this tool: when you need tag IDs to pass into start_timer or log_time. It does not explicitly list exclusions or alternatives, but the targeted use case is clear enough.

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

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

Annotations already mark the tool as read-only and open-world, so the safety profile is covered. The description adds meaningful scope detail: it lists only 'active tasks' and clarifies that tasks belong to a specifc Clockify project. It doesn't discuss pagination or ordering, but this is a minor gap for a simple read-only list.

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?

The description is two focused sentences with zero filler. The first sentence delivers the core action and scope, while the second provides the use case and prerequisite. This is an efficient, well-structured description.

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 read-only list operation with fully documented parameters and no output schema, the description covers the core action, the active-task scope, the required input source, and the downstream purpose. The mention of taskId gives enough signal for an agent to invoke the tool and use its result correctly, though an explicit return-shape note would make it complete.

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%, so the schema already fully documents projectId and name. The description adds only the note that projectId comes from list_projects, which is largely restating the schema property's origin rather than adding new semantic meaning.

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 action ('List'), a scoped resource ('active tasks belonging to a Clockify project'), and a concrete downstream use ('find the taskId for start_timer and log_time'). This clearly distinguishes it from siblings like list_time_entries, which return time entries rather than tasks.

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 explicitly says to use this tool to find taskId for start_timer and log_time, and states the prerequisite ('Requires a projectId from list_projects'). It doesn't list alternatives or exclusions, but the use-case and prerequisite make 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.

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

Annotations already mark the operation readOnly, and the description adds useful behavior: defaults to today, returns a total, and shows times in local time. This goes beyond the structured data meaningfully.

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 short sentences with no filler. The action, default range, and display behavior are presented directly and 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 a simple read-only listing tool with all optional parameters and no output schema, the description covers the key facts: scope, defaults, total, and local time. Minor gap: the format for start/end strings is not described, but the schema already provides string type and parameter purposes.

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%, and each parameter is already documented. The tool description does not add extra parameter-level meaning beyond the existing schema, so baseline 3 is appropriate.

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 uses a specific verb and resource: 'List your Clockify time entries for a period, with a total.' It clearly distinguishes this tool from sibling list_* tools (tags, projects, tasks) and timer-related tools (current_timer, log_time).

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: use this tool when you need to view logged time entries over a period. It does not explicitly name alternatives or exclusion conditions, but the resource ('time entries') is obvious against siblings like current_timer or list_projects.

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

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

While annotations indicate a write operation (readOnlyHint=false) and non-destructive (destructiveHint=false), the description adds critical behavioral detail about side effects: it explicitly states the tool does not interact with the running timer, which is beyond the annotation scope and informs the agent about concurrent state changes.

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?

The description is two concise sentences that directly state the purpose, usage context, and a key side-effect. There is no extraneous information, making it highly efficient and well-structured for rapid comprehension.

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?

The description provides essential context (back-filling and non-interference with the running timer) and is sufficient given the simple schema. It does not mention prerequisites or fallback behavior, but those are not necessary for this straightforward create operation, so it is nearly complete.

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%, with each parameter having a brief but clear description. The tool description itself does not add extra insight into parameter meanings or relationships beyond what the schema already provides, so it meets the baseline but does not exceed it.

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 the verb ('Create') and the resource ('completed Clockify time entry for a past interval'), and explicitly contrasts with the running timer, making it distinct from sibling tools like start_timer and current_timer. The phrase 'back-fill work you did not time live' unambiguously captures the intended use.

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 explicit guidance on when to use the tool ('to back-fill work you did not time live') and explicitly states what it does not do ('Does not touch the running timer'), which helps an agent decide when it is appropriate and when to use alternatives like start_timer or stop_timer.

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

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

The description discloses an important behavioral trait not visible in the annotations: starting a timer automatically stops any currently running timer. This is a meaningful side effect that could surprise an agent. The annotations already indicate a write operation (readOnlyHint=false), and the description adds context beyond that.

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 tight sentences with no filler. The main action is front-loaded, followed by a critical behavioral warning and a practical prerequisite. Every sentence earns its place.

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 tool with a simple action, 6 parameters, and a high coverage schema, the description is complete enough. It captures the one non-obvious behavior (stopping an existing timer) and tells the agent where to source IDs. The lack of an output schema is acceptable because return values are not necessary to invoke the tool correctly.

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 already provides 100% coverage, describing each parameter (including provenance like 'Project id from list_projects'). The description adds a general reminder to fetch IDs first, but this is redundant with the schema's own per-parameter notes. No meaningful new parameter semantics are introduced beyond what the schema already says.

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 verb and resource: 'Start a running Clockify timer.' It also clarifies the key side effect (stops any timer already running), which distinguishes this tool from siblings like stop_timer and current_timer. This is unambiguous and immediately scopes what the tool does.

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 use: it starts a running timer and warns that only one timer can run at a time. It also gives a direct prerequisite instruction: use list_projects / list_tasks first if IDs are needed. It stops short of explicitly comparing against log_time or declaring when not to use it, but the context is clear enough for an agent to decide confidently.

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

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

Annotations indicate this is a mutating but non-destructive, idempotent operation. The description adds useful behavioral detail by stating it reports the logged duration and gives a plain response when no timer was running, which aligns with the idempotent annotation.

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?

The description is two short sentences with no filler. The primary action is stated first, followed by the return behavior, making it easy to scan.

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 tool with one optional parameter and no output schema, the description covers the core behavior, the no-timer case, and what the caller can expect in the response. It is sufficient for an agent to select and invoke the tool correctly.

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% for the single optional parameter 'end.' The description does not add any additional meaning beyond the schema, so the baseline of 3 is appropriate.

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 uses a specific verb and resource: 'Stop the currently running Clockify timer.' It clearly differentiates from siblings like start_timer and current_timer, and adds the reporting behavior so the agent knows what the tool returns.

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 makes it clear the tool applies to a currently running timer and that it handles the no-timer case gracefully. It does not explicitly name alternatives, but the context signals and sibling names make the usage context obvious.

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