SEFAZ AP: NFC-e

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

Annotations declare readOnlyHint: false, idempotentHint: true, and destructiveHint: false. The description adds valuable context: it explains the distinction between permanent (config header) and session-only (token parameter) logins, and that the token is a JWT. It does not contradict annotations and provides behavioral details beyond the structured data, though it omits potential failure modes or side effects.

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 but dense sentence that front-loads the purpose and then lists usage options. It contains no fluff, but the semicolon-heavy structure makes it slightly harder to parse. Still, every piece of information is relevant and nothing is redundant.

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 all essential usage scenarios: how to trigger the login link, how to use a token, and the recommended permanent configuration. It does not describe expected return values (e.g., success/failure messages), but given the absence of an output schema, this is not a critical gap.

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 'token' string with no description. The description fully compensates by explaining the token's purpose (JWT for session login) and its relationship to the config-header approach. It also clarifies that the parameter is optional (when omitted, the link is provided). This adds meaning far beyond 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 clearly states the tool's purpose: to authenticate with MCP.AI for IDE agents. It specifies the action (log in, obtain token) and provides concrete usage methods, distinguishing it from vague alternatives. While siblings like 'connect' exist, the description's specificity about authentication and token handling makes its purpose unambiguous.

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 instructions on when to use the tool: call with no arguments to get a login link, or call with a token for session-only login. It also explains the preferred permanent config method. However, it does not explicitly contrast with sibling tools (e.g., 'connect') or state when not to use this tool, so it falls short of a 5.

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 declare this as read-only and idempotent. The description adds meaningful behavioral detail beyond annotations by describing exactly what the response contains in different states: authenticated true vs pending[] and connect_url vs per-install URLs. This is useful transparency for an agent expecting to interact with connection state.

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: two sentences front-load the primary purpose and then elaborate with concrete conditional outputs. Every phrase contributes meaningful information with no repetition or 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 simple zero-parameter status tool with no output schema, this description adequately explains return conditions and URL behavior. It is slightly incomplete around partial connection states, but it covers the main usage scenarios sufficiently for a basic readiness check 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 has zero parameters, so there is no parameter semantics for the description to add. Per calibration guidance, a zero-parameter tool receives a baseline of 4 because the schema and annotations already cover all input semantics.

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 returns connection status and URLs, with specific conditions ('authenticated:true', 'empty pending[]', 'connect_url'). It distinguishes itself from sibling tools like authenticate by focusing on status retrieval, but it does not explicitly contrast itself with any named alternative.

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 when to use this tool—when you need connection status and pending authentication URLs—through its conditional behavior. However, it does not explicitly state when NOT to use it or mention alternatives such as authenticate, leaving usage guidance implicit rather than directly stated.

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 are minimal (readOnlyHint: false, destructiveHint: false) and don't fully characterize the complex behavior. The description adds valuable transparency: invoke works even if MCPs are not installed, requires credentials/connect links, and may return checkout links for empty wallets. It also discloses that install has side effects (makes permanent) and writes need workspace owner/admin. However, it doesn't cover all edge cases like what happens on idempotent re-install or detailed error handling, but contextually 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 long but dense with purpose-built information for an agent. It front-loads the core flow and uses clear signposts ('Core flow:', 'KEY:', 'Search/describe flag...'). Every sentence carries actionable detail (e.g., conditions for checkout links, permission requirements). It could be seen as slightly long, but it avoids fluff and structures the multiple concerns (catalog, execution, prompts) distinctly.

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 (23 parameters, 16 action values, two major subsystems), the description covers the main behavioral contracts: how invoke handles non-installed MCPs, auth flow via connect link, billing via checkout link, permission requirements for writes, and the prompt library lifecycle. While not exhaustive (no error codes, pagination details), it covers the most critical decision points an agent would need to choose the right action and anticipate outcomes, and it complements the lack of output schema.

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 coverage is 0% and there are 23 parameters, all with generic names (message, query, arguments). The description does a good job explaining the semantics of the core `action` values and the role of mcp_id/tool_id in the flow, plus the prompt library parameters. Yet, many parameters remain under-specified (e.g., `limit`, `conversation`, `prompt_vars`), but for the primary use cases the description clarifies enough that the agent can infer parameter usage.

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 this is the official marketplace catalog and execution engine, with a detailed core flow (search→describe→invoke). It distinguishes itself from siblings by covering both catalog and execution ('in-platform catalog... AND the way to run them'). However, it doesn't explicitly name sibling tools as alternatives, and the scope is broad enough that some may confuse it with the connected MCP tools, but the purpose is clearly articulated.

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?

Explicitly gives when-to-use guidance: 'prefer invoke for a single/occasional use,' 'Use install only to make an MCP PERMANENT in the active toolkit,' and contrasts with list_tools: 'lists what is callable right now.' It also differentiates from the prompt library: 'rather than MCPs'. Alternatives are named and excluded, providing clear decision criteria for the agent.

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 provide idempotentHint=true and destructiveHint=false, and the description does not contradict them. It adds a useful behavioral requirement that the conversation array should be included for reproduction, but it does not say anything about the delivery destination, success acknowledgement, or side effects beyond sending the report.

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 only two sentences and about 17 words. It front-loads the main purpose and then gives the one critical usage instruction, with no repeated or unnecessary information.

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 conceptually simple, and annotations cover idempotency and destructive risk. The description gives the primary purpose and explains the key conversation parameter, but the missing 'context' field and lack of any information about return or delivery behavior leave the description incomplete compared to a fully specified reporting 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?

Schema description coverage is 0%, so the description must carry weight. It clarifies that 'message' contains the bug/feature/feedback content and that 'conversation' should hold recent messages for reproduction. However, the 'context' parameter is never explained, leaving one of the three parameters semantically undocumented.

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 ('Report') and names the exact objects: a bug, a missing feature, or feedback. This clearly distinguishes the tool from its siblings, none of which are about issue reporting.

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 first sentence explicitly lists the three intended scenarios: bug, missing feature, or feedback. It does not mention exclusions or alternatives, but the sibling set contains no overlapping tools, so the usage context is sufficiently 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 declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, which align with the description's 'consulta' (query) nature. The description adds meaningful behavioral context beyond annotations: it is hosted by the platform, requires no platform credentials, is paid via prepaid credit, and involves LGPD responsibility for the client. This enriches transparency, though it doesn't describe response behavior or pagination.

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 opens with the core purpose but contains redundancy: 'consulta em fonte oficial' and 'consulta informação de fontes e órgãos oficiais brasileiros' overlap. The legal and payment context is useful but could be tightened. It is moderately concise with a clear front-loaded purpose, though not as efficient as it could be.

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 covers the tool's source, hosting, credentials, payment model, and legal responsibility, which is helpful for a simple one-parameter tool. However, since there is no output schema, it does not explain what data is returned, and it also lacks input format details, leaving some gaps for an agent.

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 has a single required string parameter 'nfce' with no description, and the tool description does not explicitly define its format or expected value (e.g., NFC-e access key, number, or URL). While 'NFC-e' hints at the domain, the description does not compensate for the 0% schema coverage, leaving the agent to guess the exact parameter semantics.

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 'SEFAZ AP: NFC-e, consulta em fonte oficial' and later 'Consulta informação de fontes e órgãos oficiais brasileiros', identifying a query operation on Brazilian NFC-e data. It distinguishes from sibling tools (authenticate, marketplace, etc.) which are generic platform tools, though it could be more specific about the exact NFC-e lookup scope.

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 context for querying official NFC-e data via SEFAZ AP and provides relevant prerequisites like prepaid credit and lack of platform credentials. However, it does not explicitly state when to use this tool versus alternatives, nor does it include exclusion criteria, so the guidance is only implied.

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 declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, covering safety and side-effect behaviors. The description does not add extra behavioral details beyond the basic action, but it does not contradict the annotations. Without added context like return format or potential errors, the transparency is adequate but not enhanced.

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, clear sentence that directly states the tool's purpose without any superfluous wording. It is well-structured and easy 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?

Given the tool has no parameters and no output schema, the description fully covers what the tool does. It is complete for a simple read-only version query, providing sufficient context for an agent to 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 tool has no parameters, so the description does not need to explain any. The input schema is empty, and the description adds no unnecessary complexity. A perfect score is warranted.

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 function: 'Show the current MCP platform and adapter versions.' It uses a specific verb ('Show') and identifies the exact resource (MCP platform and adapter versions), distinguishing it from sibling tools like authenticate, connect, or marketplace.

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 mention when to use this tool versus alternatives, but given its simplicity and obvious distinct purpose (version retrieval), it may not require extensive guidance. However, explicit context could be beneficial, so a neutral score is appropriate.

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 declare readOnlyHint=true and idempotentHint=true, so the agent knows it is a safe, non-mutating operation. The description adds value by specifying what is returned (installed MCPs, statuses, accounts, catalog tool counts) and emphasizes 'current' state. No additional behavioral caveats needed for this tool.

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?

A single sentence that is front-loaded with the main purpose and then enumerates the exact output fields. Every word earns its place; no redundancy or 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?

With no output schema or parameters, the description fully conveys what the tool returns and when to use it. It covers the essential information an agent needs to decide whether to call 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 has zero parameters, so there is no burden on the description to explain parameter meanings. The baseline of 4 applies, and the description correctly omits param information.

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 ('Returns') and resource ('current toolkit state'), then enumerates the exact contents (installed MCPs, connection status, accounts, catalog tool counts). This clearly distinguishes it from siblings like show_version.

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 clearly implies when to use the tool (when an agent needs an overview of the toolkit state and connected accounts), and it distinguishes itself from siblings by listing its output. No explicit exclusions or alternative tool references, but the context is clear.

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