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

With no annotations present, the description carries the behavioral disclosure burden and does a good job by revealing the dual-mode output behavior for instance=0 versus instance=N. It does not mention error cases or units, but it makes the core conditional behavior visible beyond what the simple schema shows.

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 sentences with no filler: the purpose is front-loaded and the parameter behavior is stated compactly. Every word contributes to either identification or correct invocation.

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 one-parameter getter with an output schema, the description covers the key behavioral branch and parameter interpretation. It lacks only minor context such as source of the instance index or behavior when no devices are found, but these are not critical given the output schema and simple interface.

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 provides only an integer parameter with a default and no description, so schema coverage is 0%. The description fully compensates by explaining that 0 aggregates all batteries under 'readings' and non-zero values select a single device dict, giving the parameter meaning beyond its type and default.

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 opens with a specific verb and resource, 'Get battery state of charge,' which uniquely identifies this read operation among getters like get_pv_power and get_grid_status. It also clarifies that instance=0 returns all discovered batteries while instance=N returns a single device, adding scope and removing ambiguity.

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 by the resource name and first sentence: the agent should call this when it needs battery state-of-charge data. However, there is no explicit guidance about when to prefer this over list_devices or how to choose a valid instance value, and no exclusions or alternatives are named.

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?

No annotations are provided, so the description carries the behavioral disclosure burden. It explicitly reveals the return-shape distinction between instance=0 and instance=N, and the word 'Get' implies a read-only operation. It does not discuss failure modes or empty discovery, but for a simple status query this is adequate transparency.

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 compact and front-loaded: the core purpose is stated first, followed by the essential instance-parameter behavior in two terse clauses. Every line earns its place with no filler.

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 single-parameter read-only status tool with an output schema, the description covers the key usage and return distinction. It does not mention error handling or how meters become 'discovered', but those are minor gaps given the output schema and simple nature of the 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 schema provides only a bare integer parameter with a default, and schema description coverage is 0%. The description fully compensates by explaining the semantic difference: instance=0 returns every discovered grid meter as 'readings', while instance=N returns a single device dict. This is exactly the meaning an agent needs.

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 ('Get') and identifies the resource ('grid/AC status'). It further clarifies behavior by explaining that instance=0 aggregates all discovered grid meters while instance=N returns a single device dict. It does not explicitly compare itself to siblings, but the resource is distinct enough for an agent to distinguish it.

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 concrete guidance on how to use the instance parameter (0 vs N), which is useful. However, it does not explicitly state when to prefer this tool over alternatives like get_battery_soc or get_pv_power. The use case is implied by the resource name rather than clearly framed.

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?

With no annotations, the description carries the burden, and it discloses the key behavioral nuance: instance=0 aggregates all discovered vebus units under 'readings', while instance=N returns a single device dict. The verb 'Get' also signals a read-only operation.

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 short sentences, with the purpose front-loaded and the only parameter explained immediately after. There is no filler, repetition, or unnecessary detail.

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 one-parameter, read-only getter with an output schema, the description is largely sufficient. It does not mention a possible dependency on the MQTT tools listed as siblings, but that remains an inference rather than a clear requirement.

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 only states that instance is an integer defaulting to 0. The description adds the essential semantics: 0 is a sentinel for all units, and a non-zero value selects a single device, which is entirely absent from the 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 states the action and object directly ('Get inverter mode and state'), then clarifies the data scope with the instance rule. This makes it clearly distinct from write siblings like set_inverter_mode and from getters for other resources.

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?

No explicit when-to-use guidance, exclusions, or alternatives are provided. The agent must infer from the tool name that it is the read counterpart to set_inverter_mode, and there is no mention of list_devices for enumeration or any MQTT prerequisites.

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?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It clearly explains the two behaviors: instance=0 returns all discovered devices with readings plus total_power, while instance=N returns a single device dict. This goes beyond the schema and gives actionable behavioral context.

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 with no redundant wording. The main purpose is front-loaded, and the parameter detail follows in a compact, readable format.

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 single-parameter getter, the description covers the core behavior and output shape. An output schema exists, so detailed return structure can be obtained there. Minor gaps like units or error handling do not undermine usability.

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 only defines instance as an integer with default 0 and no description. The tool description compensates by explaining the meaning of instance=0 and instance=N, fully covering the semantic range of the parameter.

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 ('Get PV/solar charger power data'), clearly identifying the tool's function. It is distinct from siblings like get_battery_soc, get_grid_status, and get_inverter_status, which target different data domains.

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 by the resource name but not explicitly articulated. The description explains what instance values do but does not state when to prefer this tool over alternatives or mention any exclusions. Minimal but adequate.

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?

No annotations are available, so the description carries the full disclosure burden. It only states the action without mentioning that the operation is read-only, how the returned list is structured, or whether it should be used to obtain device IDs for sibling get_* tools. This goes beyond what the schema covers but still leaves key behavioral traits undisclosed.

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 that is front-loaded with the verb 'List' and contains no filler. Every word contributes to the meaning, making it appropriately concise and well-structured for such a simple 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?

Given that the tool has zero parameters and an output schema exists separately, the description is nearly complete. It would benefit from a brief note on use with sibling tools or clarification of 'visible to the server,' but these are minor gaps for a straightforward list operation.

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 has zero parameters, so there is nothing to explain. The description correctly implies that no arguments are required. Baseline for 0 params is 4, and no additional parameter documentation 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?

The description states a specific verb ('List') and a clear resource ('all Victron devices visible to the server'). It distinguishes itself from sibling get_* tools, which retrieve specific metrics, and from set_* tools that modify state. No ambiguity or tautology exists.

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 does not explicitly say when to use this tool vs alternatives, nor does it mention any exclusions. The use case is implied by the nature of listing all devices, and the sibling tools are clearly per-device queries, so an agent can infer it is for discovery/enumeration. However, no explicit routing guidance is provided.

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?

With no annotations provided, the description must disclose behavioral traits, but it only says 'Connect to MQTT broker'. It does not clarify whether the connection is persistent, whether authentication is required, what side effects occur, or if there are any limitations. This is a significant gap for a connection-establishing operation.

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 concise sentence that effectively states the core action. It is front-loaded and avoids unnecessary detail, though it could provide more context without becoming verbose.

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 simplicity of the tool (0 params) and the presence of an output schema, the description is adequate for basic understanding, but it fails to explain important context such as the relationship to mqtt_subscribe and mqtt_disconnect. The lack of usage guidance and behavioral transparency makes it incomplete for the agent to select and invoke correctly in a sequence of operations.

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 has zero parameters, so there is nothing for the description to clarify. The schema coverage is 100% vacuously, and per the baseline for 0 params, the description does not need to add parameter semantics. It correctly remains silent on parameters.

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 action ('Connect to MQTT broker') and purpose ('real-time data'), which distinguishes it from sibling tools like mqtt_disconnect and mqtt_subscribe. It is specific and unambiguous, though it does not elaborate on the scope beyond 'real-time data'.

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?

No guidance is provided on when to use this tool. It does not mention any prerequisites, alternatives, or that it should be called before mqtt_subscribe or after mqtt_disconnect. The agent is left without context for when this is appropriate relative to siblings.

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?

With no annotations, the description carries the full burden of behavioral disclosure. It only states the action, not what happens if already disconnected, whether subscriptions are cleaned up, or any side effects. This is a significant gap.

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, focused sentence with no wasted words. It is appropriately sized for such a simple operation.

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 zero-parameter simplicity, the description is adequate but lacks context about prerequisites (e.g., an active connection being required). Sibling tools imply the need to connect first, but the description itself is minimal.

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 baseline is 4. The description does not need to explain parameter details, and the schema confirms no parameters exist.

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 action: 'Disconnect from MQTT broker.' It uses a specific verb and resource, and is distinct from sibling tools like mqtt_connect and mqtt_subscribe.

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 implies usage (when you want to end the MQTT connection) but provides no explicit when-to-use or alternatives. Sibling tools context helps, but the description itself offers no guidance.

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 explicitly discloses a critical behavioral trait: 'returns an error' because it is 'not yet implemented.' This goes far beyond what annotations (none provided) would convey. It honestly tells the agent that any invocation will fail, which is exactly the kind of behavior an agent needs to know. There is no ambiguity about the tool's current executability.

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 the core action front-loaded and the critical caveat immediately following. Every word earns its place: the first sentence states the intended purpose, the second explicitly warns of non-implementation and the resulting error. There is no fluff, redundancy, or unnecessary detail, making it highly efficient for an agent to parse.

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 stub tool with a single parameter and no annotations, the description is largely complete: it tells the agent the tool is not functional and will return an error, which is the most important fact. The output schema exists, so detailed return values are not the description's responsibility. The only gap is the absence of any guidance on what to do instead (e.g., no mention of an alternative subscription tool or a future implementation date), but this is a minor omission given the tool is clearly non-functional.

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 contains one parameter, 'topic_pattern,' with no schema-level description (0% coverage). The tool description says 'Subscribe to MQTT topic pattern,' which essentially restates the parameter name without adding semantics. It does not explain MQTT wildcard syntax (e.g., '+', '#'), the expected format, or any constraints on the pattern. Given the lack of schema coverage, the description fails to compensate, providing minimal added meaning beyond the parameter name.

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 identifies the intended operation: 'Subscribe to MQTT topic pattern.' This uses a specific verb ('subscribe') and resource ('MQTT topic pattern'), and distinguishes it from siblings like mqtt_connect and mqtt_disconnect by naming a different action. However, the immediate disclaimer 'Not yet implemented - returns an error' tempers the clarity; the agent must reconcile the stated purpose with the actual non-functional behavior. It is not a tautology, and enough detail exists to understand the tool's intent.

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 an implicit usage guideline: since the tool is not yet implemented and returns an error, it should not be relied upon for actual MQTT subscriptions. However, it does not explicitly say 'do not use' or recommend any alternative tool or workflow. 'Not yet implemented' implies the agent should avoid calling it, but no when/when-not conditions or sibling alternatives are mentioned, leaving the agent to infer that this tool is currently a stub.

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?

With no annotations provided, the description carries the full burden of disclosing behavior. It does state that the operation is a write that requires confirmation, which is important context. However, it does not explain what happens upon confirmation, whether the setting persists, any side effects, or potential errors. The behavioral disclosure is minimal beyond the confirmation note.

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 sentences with no filler. The purpose is front-loaded in the first sentence, and the second sentence adds crucial operational guidance. Every word earns its place, making it highly concise and well-structured.

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 tool is relatively simple, and an output schema exists, so return values are covered. However, the description lacks context around the 'instance' parameter and does not elaborate on when or how the tool should be used in a broader workflow. It is adequate but leaves notable gaps, especially given the confirmation semantics that could be more deeply explained.

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 0%, so the description must compensate. It explains that 'current' is the maximum charge current in Amps and indirectly explains 'confirmed' via the write-confirmation note. However, it completely omits the 'instance' parameter, leaving its meaning and role unclear. The description only partially clarifies the parameters and fails to cover all three.

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 tool's action ('Set maximum charge current limit') with a specific resource and unit ('in Amps'), which unambiguously distinguishes it from sibling tools like set_soc_limit and set_inverter_mode. The verb-resource pairing is precise and self-contained.

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 mentions 'Requires confirmation for write operations,' which provides a prerequisite for using the tool. However, it does not explicitly state when to use this tool versus alternatives, nor does it provide scenarios or exclusions. The guidance is limited to the confirmation requirement, so it is only partially helpful.

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?

Since no annotations are provided, the description carries full disclosure burden. It identifies the operation as a write requiring confirmation, which is useful, but it does not explain what happens when confirmation is missing, whether the change is reversible, or any system impact. Behavior is only partially disclosed.

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 short sentences with no filler. The mode list is directly useful, and the confirmation note is a necessary constraint. It is appropriately sized for the information it conveys.

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?

Although an output schema exists, the description lacks essential context: no usage guidance, no parameter semantics for instance/confirmed, and no behavioral consequences beyond confirmation. For a mutation tool with no annotations, this is insufficient for an agent to reliably invoke it.

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 has 0% description coverage, so the description must explain all parameters. It lists the mode values but does not define them. The 'instance' parameter is entirely absent, and 'confirmed' is only implied by 'Requires confirmation,' not clearly mapped to the parameter. Significant semantic gaps remain.

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 'Set' and the resource 'inverter mode', and lists the accepted modes. This distinguishes it from sibling setters like set_charge_current_limit and set_soc_limit because the target parameter is explicitly named.

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?

No guidance is provided on when to use this tool versus alternatives. The only operational note, 'Requires confirmation for write operations', is a prerequisite rather than a usage condition, and it does not mention preconditions or alternative tools.

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 that the tool 'Requires confirmation for write operations,' which adds a key behavioral trait beyond the raw schema. However, it does not clarify how confirmation is provided (e.g., via the confirmed parameter), what happens if not confirmed, or any side effects. With no annotations, the description carries a heavier burden, but this is only partially fulfilled.

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 extremely concise: two sentences, front-loaded with the core purpose. Every sentence earns its place with no redundant or filler content.

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 an output schema exists (so return values are presumably covered), the tool has multiple parameters and a confirmation mechanism that is under-specified. The description lacks vital context about how to execute a write (setting confirmed=true?), value ranges for soc_limit, and differences from sibling set tools. This leaves the agent uncertain about safe and correct invocation.

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 0%, so the description must explain the parameters. It implies that soc_limit is a percentage, but instance and confirmed are entirely undocumented. The confirmation requirement hints at the confirmed parameter's purpose, but the mechanism and constraints are not explained.

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 'Set battery SoC limit percentage' clearly identifies the action (set) and the resource (battery SoC limit), and it is distinct from sibling tools like get_battery_soc or set_charge_current_limit. The purpose is unambiguous and directly maps to the tool name.

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 no guidance on when to use this tool versus alternatives, or any prerequisites or exclusions beyond a vague confirmation requirement. It does not mention that this is for adjusting battery state-of-charge limits in contrast to other charge-related settings.

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