UK Public Tenders MCP

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

With no annotations, the description carries the full behavioral burden. It implies a state-changing redemption but says nothing about idempotency, what happens if the session was already redeemed or is unpaid, whether authentication/ownership of the session is required, or what the call produces (a pack entitlement? credits?). Those are exactly the facts an agent needs before invoking a mutation.

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, no filler, with the action stated first and the parameter hint second. The only structural weakness is that the leading phrase "Instructions to redeem" reads like a doc pointer rather than a description of the 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?

The tool is simple (one required param, no output schema), but for a redemption flow the missing outcome information matters: what the agent gets back, whether the pack becomes usable by the sibling pack tools, and what failure modes exist. With no annotations and no output schema to fall back on, the description leaves an agent guessing at the result of a write 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?

Schema coverage is 100% and the schema already documents session_id as a Stripe Checkout id in cs_... form. The description adds only that the value comes "from checkout", a marginal sourcing hint beyond the schema. 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 names a specific resource (a paid Stripe Checkout session) but the framing "Instructions to redeem..." is ambiguous about whether the tool performs the redemption or merely returns instructions for doing so. It also gives no hint of how this relates to the sibling 'pack' tools (tenders_pack, tender_score_pack), which an agent would reasonably wonder about given the shared naming.

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?

"Pass session_id from checkout" is the only usage cue and it addresses argument sourcing, not when to call the tool. There is no guidance on preconditions (session must be paid, not already redeemed) or on when an agent should prefer or avoid this tool relative to its 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 must carry the full behavioral burden. It usefully discloses that this is a paid operation costing £0.49 and that it returns a Stripe Checkout URL rather than the data itself, but leaves unclear whether a checkout session is created, what happens after payment, and what 'Soft-Offer outbound is OFF' actually means.

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?

Very compact and front-loaded with the core purpose and return type. The trailing fragment 'Soft-Offer outbound is OFF' is cryptic and costs some clarity, but the overall definition is efficient rather than bloated.

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 paid, transactional tool with no output schema and no annotations, this covers the essentials (price, what is returned, what the pack contains) but omits the post-checkout flow and any link to 'redeem_pack', leaving an agent without the full picture of how the purchase completes.

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 'query' and 'size' (default 25, max 100) are already documented in the schema. The description adds no parameter meaning beyond the schema, making 3 the correct baseline.

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 resource ('tender-score pack') and what it contains (notices, fit_score/fit_flags, risk_flags), plus that it returns a Stripe Checkout URL. This is clearer than a bare name restatement, but it never distinguishes it from the sibling 'tenders_pack' or explains what 'score' adds relative to that 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 a paid purchase flow but gives no explicit when-to-use guidance, no prerequisites, and no routing versus siblings like 'redeem_pack' or 'tenders_pack'. An agent must guess whether this initiates a purchase or is the follow-up step after redemption.

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. It adds useful behavioral context such as a 5-result cap, 24-hour caching, and "Soft-Offer outbound is OFF," but it does not clarify read-only status, auth requirements, rate limits, or what the returned notices contain.

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 definition is short and front-loaded, with the core value proposition stated first. The final sentence about "Soft-Offer outbound" is terse and ambiguous, slightly reducing clarity despite the overall brevity.

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 two-parameter discovery tool, the description covers the result cap, source, and caching. But with no output schema and no annotations, it omits return shape, empty-result behavior, and error conditions that an agent might need.

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 query and size are already documented. The description reinforces that query can be keyword, region, or CPV and that results are capped at 5, but adds no syntax or semantic detail 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 states a specific retrieval action ("Free peek") and resource ("live Contracts Finder notices") with clear scope (up to 5 results for a query). It signals a limited free preview, but does not explicitly name or differentiate against sibling tools such as tenders_pack.

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 "Free peek" implies this is a limited preview, suggesting use when only sample results are needed. However, there is no explicit guidance on when to use this versus tenders_pack, tender_score_pack, or redeem_pack, and no exclusions are 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?

With no annotations, the description does useful work by disclosing the £0.49 cost and that the call yields a Stripe Checkout URL rather than the notices themselves. But it omits whether calling it charges anything, what happens after checkout (presumably redeem_pack), and leaves 'Soft-Offer outbound is OFF' undefined.

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 that are front-loaded with the core fact (paid notices pack returning a checkout URL), so length is not a problem. The second sentence is opaque internal jargon that consumes space without conveying anything an agent can act on.

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 annotations and no output schema, the description must carry the full workflow, yet it never explains what the pack delivers after payment, how redeem_pack fits, or whether repeated calls create multiple checkouts or charges. For a paid, multi-step tool that is a significant 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?

Schema description coverage is 100%: 'query' (keyword, region, or CPV code) and 'size' (default 25, max 100) are already documented in the schema. The description adds no meaning beyond that, so the baseline of 3 applies.

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 identifies the resource as a paid pack of Contracts Finder notices and states the return value is a Stripe Checkout URL, which is more specific than a tautology. However, it never says what the pack actually contains or how this differs from the sibling tender_score_pack, leaving the agent to infer the distinction from the word 'notices' alone.

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?

There is no statement of when to use this versus tenders_discover (search) or tender_score_pack, nor any prerequisite such as requiring a specific tenant or wallet. The only conditional-sounding sentence, 'Soft-Offer outbound is OFF', is unexplained jargon rather than usable guidance.

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