fresh-feeds — trending/new/changed MCP servers + x402 change-data API

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

With no annotations provided, the description carries the full transparency burden and does so well: it states the tool is read-only, free, uses a maintained sample of the first agentIds, and flags specific risk types. It also discloses the score range and the cross-referencing logic, giving the agent a clear behavioral model of what the tool does.

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 with the 'Verify-before-you-pay' tagline. It packs substantial information into four sentences without redundancy.

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?

Despite lacking an output schema and annotations, the description covers the tool's purpose, usage patterns, input semantics, output score range, and limitations (sample-based coverage). This is sufficient for a relatively simple two-parameter 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 already has 100% coverage with detailed descriptions for both parameters, so the baseline is 3. The description adds meaning by clarifying the OR relationship between agentId and address, and the omit-both-to-list-sample behavior, which is not fully captured in 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 performs a read-only risk assessment (0-100) for ERC-8004 agents, cross-referencing declared identity against on-chain control. This specific verb+resource distinguishes it from sibling registry tools, which focus on MCP registry status and verification.

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 opens with 'Verify-before-you-pay,' explicitly signaling the intended use case: checking an agent before transacting. It also explains the parameter selection logic (look up by agentId or address, omit both to list the sample), but it does not name any alternative tools or provide explicit when-not-to-use 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?

With no annotations, the description carries the burden for behavioral disclosure. It implies a read-only operation with 'Freshness/health' and states it is 'Free,' but it does not explicitly confirm it has no side effects or require any special permissions. For a simple status read this 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 one concise, front-loaded sentence plus a standalone 'Free.' note. Every word adds value, with no filler or redundancy.

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, parameterless tool, the description adequately covers what the tool reports. However, 'both feeds' is ambiguous without additional context, and it does not describe the output structure (e.g., JSON object). The listed data points partially compensate for the lack of an 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?

The tool has zero parameters, so the baseline is 4. The description does not need to add parameter details since there are none to document.

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 reports 'freshness/health of both feeds' with specific data points (snapshot ages, counts, change-baseline dates). It is a clear verb-less status description but does not explicitly differentiate from sibling tools or clarify which feeds are meant.

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 extra note is 'Free,' which is about cost, not usage context. There is no mention of situations where a sibling tool would be more 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?

With no annotations, the description carries the burden and does well by disclosing the key behavioral trait 'PAID (x402)' and describing the output as 'x402 payment instructions.' It doesn't detail side effects or security requirements, but the core paid nature and data scope are transparent enough for this simple 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?

Two concise, front-loaded sentences with no fluff. The paid indicator is prominent, and the alternative is mentioned in a single, clear directive.

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, no-output-schema tool, the description fully explains the return type and purpose, and even provides a usage direction. Nothing essential is missing.

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 and schema coverage is 100%, so there is nothing for the description to add. The baseline for 0 parameters is 4, and the description doesn't repeat irrelevant param details.

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 x402 payment instructions for the FULL deduped, quality-scored MCP registry snapshot,' naming the exact resource and action. It also implicitly distinguishes itself from search_mcp_registry by emphasizing the 'FULL snapshot' and paid nature.

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?

Explicit guidance is given: 'Use search_mcp_registry (free) for targeted lookups.' This tells the agent when to use this paid tool versus a free alternative, satisfying the dimension fully.

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 burden. It discloses that the endpoint is PAID and involves x402 payment instructions, and that it returns delta information. However, it does not explain the payment flow, rate limits, or response format, leaving some ambiguity about what exactly is returned.

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, front-loaded sentence that conveys the paid nature, the resource, and the delta scope without unnecessary verbiage. Every part 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 simple one-parameter tool with no output schema and no annotations, the description provides the essential purpose and usage hint, but it leaves out details about the exact return payload and the mechanics of the x402 payment process. It is adequate but has gaps.

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 for the single parameter is 100%, with the schema already describing the 'since' parameter and referencing feeds_status. The description only adds the phrase 'since a daily baseline,' which aligns but does not provide new semantic meaning 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 returns x402 payment instructions for the registry delta (added/removed/changed servers) since a daily baseline. This distinguishes it from sibling tools like get_registry_highlights or get_mcp_registry_snapshot, which focus on highlights or full snapshots.

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 phrase 'the cheap habit endpoint for repeat callers' indicates when to use this tool, implying it is for frequent, cost-sensitive delta requests. However, it does not explicitly name alternatives or state when not to use it, but the context is reasonably 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?

No annotations exist, so the description must carry the burden. It discloses that it is free and includes snapshot freshness, providing some behavioral context. However, it does not explicitly state read-only nature, return format, or any side effects. For a simple read tool, this is adequate but not thorough, hence a 3.

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 front-loads the key points (top 10, quality score, trending, freshness). 'Free' is a short, relevant addition. Every word earns its place with no waste.

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, parameterless tool with no output schema, the description adequately covers what the tool returns: top 10 by quality score, trending categories, and snapshot freshness. It is not overly detailed but sufficient for the tool's simplicity. A 4 is appropriate because it gives a clear high-level picture without needing more.

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, and schema description coverage is 100% vacuously. The description does not need to add parameter semantics. Per the rubric, zero params baseline is 4, and no additional info 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 clearly states it retrieves the top 10 MCP servers by quality score, along with trending new arrivals/score risers and snapshot freshness. This specific verb+resource combination ('get registry highlights') with listed contents distinguishes it from sibling tools like get_mcp_registry_snapshot or get_registry_changes.

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 as a quick overview of top/trending servers, but it does not explicitly state when to use this tool versus alternatives or provide exclusions. 'Free' is a cost note, not usage guidance. Since it is implied rather than explicit, a score of 3 fits.

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 behavioral disclosure. It only indicates the tool returns payment instructions, with no mention of side effects, authentication needs, rate limits, or return format. This is minimal and leaves significant gaps for an agent.

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, compact sentence that uses 'PAID (x402)' as a contextual prefix and immediately states the action and scope. Every word contributes meaning, with no redundant phrasing or fluff.

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 has no output schema and no annotations, so the description must explain the return value and behavior fully. It only says 'returns x402 payment instructions,' leaving the structure, pagination, and exact contents of the snapshot undefined. This is insufficient for an agent to predict the tool's output.

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 fully complete. Per the rubric, the baseline for zero parameters is 4, and the description adds context by specifying the full liveness-probed feed, which helps clarify the scope of the data returned.

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 x402 payment instructions for the full liveness-probed services feed, using a specific verb and resource. It distinguishes itself from sibling tool list_x402_services by emphasizing payment instructions and the full feed 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?

No explicit guidance on when to use this tool versus alternatives like list_x402_services or get_mcp_registry_snapshot. The 'PAID (x402)' prefix hints at a paid-service context, but it does not state when to choose this over other tools or any exclusions.

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 behavioral disclosure. It discloses liveness-probing behavior, the guarantee that services are up and demanding payment, and the free limit of 25. It implies read-only nature via 'list' and 'before you pay it', but does not mention sorting or response format, leaving some minor gaps.

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, front-loaded with action and purpose, ending with alternative tool reference. Every clause adds value without waste.

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?

Simple tool with two optional params and no output schema; description covers purpose, constraints (free, max 25), behavioral guarantee (liveness-probed), and alternative for full feed. Minor gap: no mention of return shape or default order, but sufficient for basic use.

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 100% for both optional parameters (limit and payable_only) with descriptions. The description adds the 'up to 25' cap which aligns with limit's maximum, but provides no additional semantic detail beyond what the schema already states.

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?

Description uses specific verb 'List' and names the resource as 'x402 services discovery catalog's active edge, liveness-probed'. It clearly distinguishes from sibling get_x402_services_snapshot by noting the free/paid split and feed 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?

Explicitly recommends get_x402_services_snapshot for the full liveness-probed feed, and states this tool is free with up to 25 results, giving clear when-to-use and when-not-to-use guidance. This directly addresses alternatives among 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 full behavioral disclosure. It mentions the registry is deduped, quality-scored, refreshed every 30 minutes, free, returns up to 25 results, and lists returned fields (score, status, remotes, packages). This exceeds minimal expectations.

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 sentences, all substantive and front-loaded with the core action. Each clause adds value: defining scope, return details, and alternative tool. 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?

The description covers purpose, limitations, return content, maintenance characteristics, and the paid alternative. For a simple search tool with fully documented schema and no output schema, this is complete and self-sufficient.

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 descriptions cover both parameters 100%, including constraints (limit 1-25, default 10) and query semantics (case-insensitive substring, omit for top servers). The description adds no extra parameter information, 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 clearly states the tool searches the MCP server registry by name/title/description, using a specific verb and resource. It also distinguishes this tool from the sibling get_mcp_registry_snapshot by noting that the snapshot returns the full corpus.

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 specifies when to use this search tool versus an alternative: 'For the FULL corpus (~1500 servers) use get_mcp_registry_snapshot (paid, x402).' It also notes the free nature, result limit, and that omitting the query returns top servers by quality score.

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 discloses key behavioral traits: the report is based on cached signals (not live), uses registry status/endpoint presence/freshness, and produces a transparent 0-100 grade. It also notes that the live probe is only available in the paid version. This is solid but doesn't mention potential staleness or other limitations.

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 the first sentence front-loading the core purpose and the second clarifying the paid alternative. No unnecessary words; every sentence contributes to understanding.

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 (1 param, no output schema, no annotations), the description is complete: it covers the output (grade), the data sources (cached signals), the scope (one registry server), and the tier difference. The reference to search_mcp_registry in the schema covers prerequisites.

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 100% and the schema already provides a meaningful description of the 'server' parameter (registry server name, use search_mcp_registry). The tool description does not add significant parameter-specific meaning beyond what the schema states, so it meets the baseline of 3.

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: producing a free preview-grade trust report with a 0-100 grade from cached signals. It distinguishes itself from the paid full report (verify_mcp_server_report) by explicitly naming the alternative, so there is no confusion.

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 contrasts this free preview with the paid full report (verify_mcp_server_report), indicating when to use each. It also references search_mcp_registry (in the schema description) as a prerequisite for finding server names, which guides usage.

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 usefully reveals that the tool is PAID (x402) and that it returns payment instructions rather than the report itself. However, it does not explain what happens after payment, whether the operation is reversible, or any side effects, leaving significant gaps for a payment-related 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?

The description is a single sentence that immediately front-loads the 'PAID' nature and clearly states the core function. Every word earns its place, with no filler or redundant phrasing.

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 simple with one parameter and no output schema, so the description does explain the return value (x402 payment instructions). However, it lacks details on what the instructions contain, how to complete payment, and how this relates to verify_mcp_server, leaving the agent with important unanswered questions about using the tool in a workflow.

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 already provides full coverage with a clear description for the 'server' parameter. The tool description's phrase 'for one registry MCP server' aligns with the schema but adds no new meaning or syntax details, 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 clearly states the tool returns x402 payment instructions for the full verification report of one registry MCP server. It explicitly mentions the report includes a LIVE endpoint probe and component breakdown, which distinguishes it from the sibling tool verify_mcp_server that likely runs the verification itself.

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 by indicating it's a PAID operation and that it's for the FULL report, hinting that a lighter or free option may exist. However, it does not explicitly state when to use this tool versus alternatives like verify_mcp_server, nor does it provide any exclusion criteria or prerequisites.

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