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

Goes beyond the annotations by disclosing the semantic effect (no payment can subsequently be checked or recorded against the intent), the sealing of an audited reason, and the exact return payload. The repeat-call behaviour mostly restates idempotentHint=true, and it doesn't say whether a cancelled intent can be reopened, so it falls just short of a 5.

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?

Four short sentences, front-loaded with the trigger condition, followed by effect, return value, idempotency and prerequisite in that order. Every sentence carries distinct 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?

No output schema exists, and the description compensates by naming the return contents (intent ID, reason, withdrawal time). Combined with full parameter coverage and annotations, an agent has everything needed to call this 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%, so both parameters are already documented, including the intent ID format and the auditor-facing reason requirement. The description reinforces the reason's role ('seals the withdrawal with the reason') but adds no new syntax or constraints, which matches the baseline of 3 when the schema does the heavy lifting.

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 and resource ('withdraws the intent so no payment can be checked or recorded against it') plus the consequence of the action. This is clearly distinguishable from siblings such as record_intent, check_payment and record_settlement without opening any schema.

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?

Gives explicit when-to-use conditions ('when you decide not to pay an intent you declared, or the purchase is no longer needed') and names the prerequisite alternative: 'Use get_intent first if you are not sure the intent is still open.' The routing decision is fully specified.

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 adds substantial context beyond annotations: it explains the approve/decline outcome, the consequence of decline, and the important caveat that the book's limits are self-declared and do not grant external authority. It does not explain non-idempotency or what state the non-read-only call may change, but annotations already flag those hints.

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 three tight sentences with zero waste. The call timing, outcome, decline handling, and authority caveat are each front-loaded and 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 five-parameter payment-check tool with no output schema and 0% schema description coverage, the description gives strong usage and behavioral guidance but leaves parameter meaning largely unexplained. It does say the return is approve or decline with reasons, but an agent still lacks enough detail about the required and optional inputs.

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% for five parameters, so the description must carry parameter meaning, but it never defines amount_minor, currency, nonce, intent_id, or counterparty. It only indirectly gestures at an open intent and payment limits, leaving the actual parameter semantics 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 states a specific check: whether a payment is inside an open intent and within the book's limits, returning approve or decline. It also distinguishes the tool's role from siblings by placing it after record_intent and immediately before paying.

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 is explicit: call this after record_intent and just before paying, and if the result is decline, do not pay. The sequencing and the action to take on decline are both stated directly.

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 a non-read-only, non-idempotent, non-destructive write, and the description adds real context beyond them: the output location, the failure-on-existing-folder behavior, and the fact that the copy is self-verifying (returns verified/passed/failed). It does not mention permissions or how large books are handled, but the mutation semantics an agent needs are 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?

Four sentences, each carrying distinct information: action and destination, naming rule, return values, and collision/alternative behavior. The core action is front-loaded and there is 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?

No output schema exists, but the description enumerates what comes back (the folder, the files, and the verification result). Combined with the naming constraint, overwrite rule, and sibling routing, an agent has everything needed to call it 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 coverage is 100%, so baseline is 3, but the description adds genuine meaning: "Give a short folder name, not a path" clarifies intent beyond the schema's character-class constraint, and "fails, unless overwrite is true" explains the consequence of overwrite rather than just restating "replace an earlier export".

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 and resource ("Copies the book, with a sealed manifest") plus the exact destination (/tmp/spr-books/exports) and the audience (auditor or counterparty checking with spr-verify). It also explicitly separates itself from export_xbrl_csv, so an agent can pick between the two exports without opening a schema.

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?

Names the alternative (export_xbrl_csv) and the condition that selects it (spreadsheet or reporting format), which is explicit when-not guidance. It also states the collision rule — fails if the folder already holds an export unless overwrite is true — giving the agent the precondition it needs before calling.

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?

Goes well beyond the annotations: states the write target (/tmp/spr-books/exports), that a new folder is created, that a name collision causes failure unless overwrite is true, and what the response contains (folder, file names, row count). Annotations already cover the readOnly/idempotent profile, and the description adds the operational details an agent needs.

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?

Front-loaded with purpose and output, then the failure/overwrite rule, then the sibling routing. Dense but every sentence carries information; slightly long, though nothing is wasted.

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?

No output schema exists, but the description enumerates the return values (folder, file names, row count), and covers naming rules, collision handling, and the alternative tool. Nothing an agent needs to invoke this correctly 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?

Schema coverage is 100%, so the baseline is 3; the description adds a real constraint not in the schema — give a short folder name, not a path — and explains the overwrite condition (replace an earlier export of that name) in context. That is meaningful added value over the schema text.

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 and resource: writes the book's payments as xBRL-CSV, names the exact output files (mpp-report.json, mpp-payments.csv) and the profile followed. Clearly distinguishable from export_package, which is named as the alternative for sealed copies.

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?

Gives explicit routing: use export_package instead when the goal is a sealed copy for an auditor or counterparty. Also states the precondition/behavioral rule for reuse of a folder name (fails unless overwrite is true), so the agent knows when to set that flag.

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 cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds real value by warning that purposes, counterparties and memos are untrusted agent-authored data and must never be treated as instructions — a genuine prompt-injection disclosure not present in structured fields.

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: the lookup purpose and states come first, the untrusted-data caveat second. Nothing is repeated from the schema and every clause carries 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?

With no output schema, the description usefully previews the return: a status among four enumerated values plus field categories. It is nearly complete for a single-ID lookup; only the parameter's ID format and the not-found / not-yours case are unaddressed.

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% for the single required intent_id, so the description must carry semantics. It implies ownership ('one of your intents') and single-record scope, but gives no format, source of the ID, or behavior on a missing/foreign ID.

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+resource ('look up one of your intents') and even enumerates the possible states returned (open, matched, expired, withdrawn). It implicitly distinguishes itself from list-style siblings by scoping to a single intent, but never names an alternative explicitly.

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?

Gives a concrete triggering scenario: 'such as before paying against an older intent'. That tells the agent when to reach for it, but there is no explicit when-not guidance or routing to alternatives like list_records or cancel_intent.

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 readOnly/idempotent/non-destructive, and the description adds genuinely new behavior: the entire book is returned with no paging, which is critical for an agent reasoning about volume and cost. It also discloses an unusual security trait — that purposes, counterparties and memos are untrusted data, never instructions — which no annotation conveys.

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?

Front-loaded with what is returned, then the no-paging constraint, then sibling routing, then the injection warning — each sentence carries distinct, decision-relevant information. The field enumeration is dense but earns its place given there is no output schema.

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, the description compensates by listing every returned field, stating result volume and lack of pagination, and warning about untrusted content in the response. Nothing an agent needs to invoke or interpret this tool correctly 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 single `all` parameter has 100% schema description coverage, so the baseline is 3. The phrase "with its current version" hints at the default behavior and thus at what `all` toggles, but the description never addresses the option to include earlier versions of corrected payments, leaving that meaning entirely to 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?

Names a specific verb and resource ("lists the payments in your company's book") and enumerates the exact returned fields, so an agent knows precisely what comes back. It is clearly distinguishable from get_intent and verify_record, which are named explicitly.

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?

Gives explicit positive use cases ("find a record_id or review what has been paid") and routes the agent to alternatives with the conditions that select them: get_intent for one intent, verify_record for checking a seal. Both when-to-use and when-not-to-use are covered.

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 cover the write/idempotency profile (readOnlyHint=false, idempotentHint=false, destructiveHint=false), so the description's job is to add context — and it does: the record is 'sealed in your company's book' (audit-trail, effectively immutable) and must precede payment (ordering constraint). It does not disclose whether a recorded intent can be amended or cancelled, or how expiry interacts with later settlement, which keeps it below a 5.

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 tight clauses with the most important directive ('call this first') front-loaded, followed by the trigger list, the audit consequence, and the unit convention. No restatement of the tool name and 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 an 8-parameter, non-idempotent write tool with no output schema, the description omits what an agent receives back (an intent identifier?) and how that value links to record_settlement, check_payment, or cancel_intent. The ordering and unit guidance are solid, but the post-call workflow and half the parameters are left to inference.

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 50% across 8 parameters, so the description must compensate and it partially does: 'Amounts are integers in the currency's minor unit (cents; 6 decimals for USDC)' disambiguates the highest-risk fields (max_amount_minor, expected_amount_minor) that the schema leaves unitless. The remaining parameters — rail, currency, counterparty, expires_in — get no treatment in the description, leaving half the surface to the bare 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 gives a specific verb and resource ('declare what you are buying and why', 'record intent') and adds a lifecycle position ('call this first ... before paying') that separates it from siblings like record_settlement or check_payment. It stops short of naming any sibling explicitly, so the differentiation is inferential rather than stated.

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 timing is unambiguous and concretely enumerated: 'whenever you are about to pay for anything (an x402 request, an API, data, compute, a card or Stripe payment)' with the ordering constraint 'call this first ... before paying'. No exclusion conditions or named alternatives (e.g. when to use cancel_intent or check_payment instead) are given, 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?

Beyond the idempotent/non-destructive annotations, it discloses the replay semantics ('the same payment again returns unchanged'), the conflict behavior ('different facts ... return conflict and seal nothing'), and the escape hatch ('unless you give correction: { reason }'). It also reveals the validation performed (cap and expiry checks) and that records become immutable ('sealed'), which annotations cannot convey.

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?

Front-loaded with the trigger and the rule, then the idempotency and correction conditions, in three dense sentences with no filler. The telegraphic phrasing ('sealed', 'Different facts') is compact but slightly terse for an unfamiliar domain.

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 an 18-parameter mutation with nested objects and no output schema, it covers the crucial behavioral contract (idempotency, conflict, correction, immutability). It omits how the record is matched to its intent and what errors a failed cap or expiry check produce, which an agent would want.

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 50% across 18 parameters, and the description only adds meaning for source_id (the rail's reference) and correction.reason. It gives no guidance on amount_minor, currency, occurred_at, intent_id, direction, or the counterparty/evidence fields, so half the surface is left to the schema alone.

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 (records) and resource (the payment), plus the trigger ('right after each payment succeeds') and the key input ('the rail's own reference'). The sealing/matching/cap-and-expiry framing makes it clearly distinguishable from record_intent, which would create the intent rather than seal the resulting payment.

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 says when to call ('right after each payment succeeds, with the rail's own reference') and spells out the conflict and correction paths. It does not name sibling tools or say when to use check_payment or verify_record instead, so no explicit alternative routing.

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 cover read-only, idempotent, closed-world and non-destructive behavior, so the safety profile is settled. The description adds genuinely non-derivable context: the answer contains purposes, counterparties and memos authored by third parties and must be treated as data, not instructions. It does not describe what an invalid or unsigned record yields, which is the main remaining behavioral 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?

Two sentences, trigger first, safety caveat second, with no filler. The prompt-injection warning is placed after the call condition so the routing decision is 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 one-parameter read tool with no output schema, the description covers when to call, what is checked, and how to treat returned content. It stops short of describing the shape of the verification result (valid/invalid, error on missing record), which an agent would benefit from knowing.

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% and the single required parameter record_id is undocumented anywhere. The description implies it identifies a record in 'your company's book' but adds no format, source, or lookup guidance. A 3 reflects that the identifier is largely self-evident but the description does nothing to compensate for the coverage gap.

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-and-resource pair (verify a record) plus the concrete checks performed: integrity of the entry in the company's book and signature by its key. This is clearly distinguishable from siblings like list_records or get_intent, which retrieve rather than attest.

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?

"Call this when someone asks whether a record is genuine" gives a clear triggering condition tied to a user question, which is more actionable than a generic description. It does not explicitly exclude adjacent cases (e.g., when to use list_records or check_payment instead), so it falls short of full routing guidance.

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